The sickeningly violet undergrowth stretched in all directions. It was a collaged forest of trees that looked the same, smelled of pine and echoed Amy's bathroom-quality singing off the nearby hills. She started by just shouting 'hello' over and over into the silence, but that had got boring. There was only so many times she could listen to herself say 'hello' before feeling like an utter idiot. They'd have heard her shouting the first time, or the second, so when no-one replied by the fiftieth 'is anyone out there?' they probably weren't going to. Next, she'd tried some rap that spoke to her current condition and announced to the forest that her knees were weak, arms were heavy but that was as far as it would go. She forgot the second verse, began ad-libbing and then gave up. She couldn't freestyle to save her life. Now she'd been reduced to humming to herself to stave off the silence.

It had taken an hour of walking to find a dirt road that seemed to be going in the right direction. That had been a while ago. She gave thanks to the gods of the temple-bank for making the choice between her new hundred pound leather boots and bare feet easier. Trampling through uneven rock and leaf litter had proven a sure-fire way to get blisters. She was sure she had some by the time she found the track. The bloody shoes weren't any closer to breaking in either, and she was beginning to suspect they were half a size too small. Still, for now, they stayed.

Any was well known to have a sense of direction that was poor at the best of times. Give her slow blood loss and a preoccupation with keys and she had no idea of where her beloved temple-bank ruins might be any more. If she really had to, she could always try a desperate attempt to track the landmarks, trees and guess her path. In reality executing that idea was wishful thinking to the extreme, especially when you're constantly dripping new tracks, the leaf-litter undergrowth is a collage of identical purple, there are no landmarks, and you've never tracked anything in your life. No, there was no way back now, no way to double check if there might've been another way out. Amy would have to make it to the glittering magical spires with only the power of terrible homemade lyrics and dusty shoes that had once been a more fetching shade of brown. The steep valley evened out a little after another few minutes trudge and for the first time in hours she spotted something man-made.

She slowed when she approached this first piece of non-nature. It was a signpost. A wooden signpost for something. At least she assumed that whatever the hell was written on it was a form of language. She counted fifteen runes and four unidentified squiggles on the three signs that pointed in different directions. One sign for each branch of the fork, one back the way she came. Great. Underneath were remnants of something that may or may not have been someone scratching their initials into the post with a knife in runic. Well, she was walking towards two-runes, squiggle, four-runes, so maybe that was good? It could have said 'fastest route home for key-ridden students' in the local language. At least there was some form of life and culture here to explore, and interesting astrophysical phenomena like the Sun being glued in place over the horizon.

Annoying as it was to have so few signs of civilization she had to admit they took care of their forests. Not a crisp packet in sight. She wasted some time trying to decipher whether two interlocking squares meant anything, or whether a crossed squiggle was a bad omen. No idea. Her left arm had gone from shock and pain, to crawling with ants to being freakishly just plain numb once again, and under the dried grime it was probably pretty damn pale. Calm down. You're in a world you've entered seemingly based on an old screensaver you found online and kept for years. There are worse problems than the arm like being stuck here forever and dying alone in the silence. These runes aren't going to help you. Amy took out 'airplane mode' for a moment and scrawled her name down the signpost using the teeth. 'Amy was here. Help.'

In reality the runic trail was helpful for anyone with a remote knowledge of local customs. It suggested that the centre of the local town was only about three bakres away, a bakre being close to one and a quarter of a mile, give or take a few feet and a metric shit-tonne. The grand unity of all measurements being made in bakres would have just confused her if she'd known about it. Bakres measure both distance and weight. And pressure. Context is key - or rather, um, essential. Such quirks went unnoticed by Amy as she walked the next one. Unadulterated forest ended as she started passing ruins that were pretty temple-bank like. Homes and overgrown streets stretched into the darkness on either side and ended engulfed in the canopy some quarter-bakre beyond. Why her dirt track was well maintained and not similarly overgrown like the homes was a mystery. There was the same thick sandstone brickwork and collapsed roof tiling for as far as she could see down the valley, roofs poking out here and there. Only a few seemed intact enough to have a second, or third, floor and what were once presumably pretty grand entrances were now frustratingly door-less, and structurally questionable.

She poked around inside for a little while when she spotted a stately home that looked a bit better than the others. She even shouted a cautious 'hello'. Whatever interior design had once existed there was long gone from the sandstone rooms. For the sake of trying it, she pulled out the car key, stood in the entrance of the monolithic house and mimed her way through opening a door-full of air. She tried it again, this time with her eyes closed, and flipped the key in her good hand awkwardly as she was twisting to give it a full turn instead of faking it and only twisting it halfway. She pressed the unlock button on the car key, which did nothing but flash a little red light on the fob, then went for the lock button and finally the one to open the boot. They did as expected, nothing. She tried the same with another key. Finally to give it some real emotion she pulled out the biggest one she could find. The black mess of teeth of the 'end' key would do the trick if any could. She tried pretending she was still fourteen and at home unlocking her room. Even more so back then than now her brother had been a menace she couldn't let in there, ever. She turned the key, pulled it out of the keyhole and opened the pretend air handle, furrowed her brow in concentration about door-y things and considered whispering 'open sesame' for good luck. She imagined stepping through the open door to her room and walked the two steps through the threshold, then turned around. She opened one eye as not to scare her imaginary air-door into falling apart. She opened the other eye and looked out onto the same violet undergrowth. Nothing worked. The keys remained useless, both the real ones she'd tried miming for five minutes and the one she'd used for her room back home a few years ago. Her brother bought lock picks. It was probably for the better that 'end' hadn't worked, anyway.

Soon other tracks joined hers and slowly widened the road into an avenue sprinkled here and there with small paving tiles. They were tiles that seemed like they would have once made a pretty fancy road surface. If you could afford to pave the street with glazed flowers and pictures of dragons on a backdrop of perfectly smooth metal plates, you were doing better than Exhibition road and could afford some nice doors and locks to match. That was assuming this civilization even used locks. The further in she walked, the less worn the road and more complete the houses, temples or whatever they were became. She could see the motif of the road paving now as it stretched from one side of the avenue to the other, though seeing it wasn't equivalent to making sense of it. She looked down and walked from side to side. It included a set of intertwined branches, dragons, animals, geometry and bizarrely-interwoven fish that were a feast for the eyes. A gaudy feast that she imagined wouldn't sit well if you had a bite.

Closer to the spires the forest thinned out into streets that slowly turned less post-apocalyptic. The city centre was definitely closer, and less gaudy than feared. Amy scrambled over some of the rubble in the street and ignored the developing blisters in the fuchsia-sandstone silence. How much set theory would she be catching up on at this rate? Best not think about it. Most of all right now Amy regretted not stealing Cajun chicken and a few miniature bottles of red wine in the fray.

She marched onwards down the turns of the main avenue and reached the final stretch into the city. What had once been a dirt track some miles in the hills was now a thick motorway of stencilled dragon motifs and smoothly-chromed high-speed roads. Beyond soared the high boundary between ruined suburbs and the entrance to the city of runes itself, a shaded wall stretching left and right high above the decaying sandstone apartments as far as she could make out. Attacking that wall could only end in neck strain. In the impressionistic art of her screensaver the city had been painted as being in the distance shrouded by shrubbery and well-placed leaves presumably both to save time on drawing details and to add mystery. Thinking back she could picture the place where she must be standing now. On her laptop she'd be snugly next door to an icon for the internet browser and a file of her best and freshest memes. In that case, she should have been able to spot the temple-bank from here but try as she might it blended in too well in the violet hills. Maybe she'd see it from the walls and get a sense of how far she'd made it. Part of her felt sad that she couldn't suspend childlike disbelief at the wall. Even a medieval-looking magic screensaver realm shouldn't have the technology to upturn the Hoover Dam.

"Hmm" she said to no-one in particular approaching the behemoth and gave an incredulous glance towards the camera she sometimes liked to imagine was filming her reaction. This moment of her life belonged in a sadistic sit-com somewhere. Today's episode 'When Windows become doors', filmed in front of a live studio audience. The archway through the city walls could fit a lorry lengthways with room to spare. She passed its decorative portcullis and she wasn't surprised to find the walls were covered in carvings. The spired city on the other side was equally deserted, and well-maintained. No people, or animals. Fresh posters on the inner side of the archway advertised what she assumed to be 'the best prices on squiggle, square, rune, rune in the whole city'. A second showed a man with four arms gazing at two small rabbit-like creatures fighting in an arena. He looked pretty serious about it. The archway opened up to a market square that looked, for the most part, pretty ordinary. Nearby a fountain statue of a half-tonne otter on a log gurgled water from its mouth. She cupped her good hand and took a cautious sip from the greyed pool, then washed the grime off her arms and shoulder. That felt a lot better. Amy sat for a while, and dropped the satchel. There were doors here. Good. Now it was time to think through the steps of a plan that had been slowly forming in her mind over the past few hours, starting with checking what keys could get her home.

"So, this how make you call sentence, yes? Strange?" Amy jumped at the resonant voice. She brandished the satchel waiting to kitten-slam whoever the hell just whispered to her.

"Hello? Who are you?" She heard herself say it and realized it sounded awfully like a line from a horror film.

"Please, slow speak me." The disembodied voice seemed hurt.

"Speak slowly? Okay. Who the hell are you and what is up with the accent? Ichor?"

It struggled to get its words out.

"What?" asked Amy.

"I said I'm an otter. Or close to it, anyway. Learning English."

"You're the statue," answered Amy and turned to face the fountain. "Why am I talking to a statue of an otter? No, really. Please. Enlighten me." Amy's voice echoed off the sandstone.

"Hard to explain right now. Need time. You try learning English, eh? Kavaldish much easier. Simple runic lettering. Regular. Ordered. Tautology?" The otter voice muttered and reorganized its knowledge of the English language.

"And why are you smiling vomiting out water all the time?"

"Believe me, it's not as fun as it looks up here, and I'm not really here anyway," came the half-drowning reply. "I'm a city guide, I welcome visitors and aspire to learn their language, crude or not. See that inscription down there?" Amy looked. It was, as always, a rather fetching group of runes. "The first one's my name, the rest explains all this." It seemed to gain its confidence in English.

"What's your name?"

The otter made a deep rumbling sound that it seemed quite pleased about.

"I'll just stick to what I know."

"That's for the best," whispered the otter unmoving.

"Has your voice ever heard of personal space? Move back a bit."

The voice obliged and centred itself on the fountain. "Now then," the otter gargled. "You've had quite a wild ride to get here, haven't you? Wilder than most."

Amy looked herself up and down. "Yeah. Sorry for bleeding on your pool."

"There's a chemist's around here somewhere if it'll help, look for a sign..." the otter's voice she imagined was wincing at the butchered translation "...of what you call four squiggles followed by a picture of a hawk. It's been a few pseudo-centuries, so I can't quite recall where it is."

"I need a lock, not a chemist's," said Amy. "And where is everyone?"

"Doors are no trouble. Judging from your memories the decay's a lot worse out there. I doubt in reality it's been more than ten real minutes since everyone left, though I'll admit those ten have dragged on a bit." The otter decided not to worry Amy about the bakre to minute conversion rate. It only made tourists' heads spin, and she seemed already unsteadily low on blood.

"Judging by my memories?" Amy looked about the market square. It was fertile with doors, as were the streets leading from it.

"Oh come on, don't sound so upset. You can't expect me to learn English and not poke around. Otherwise I wouldn't know what your words mean to you."

"That seems intrusive."

"I suppose it would, but there is a disclaimer on the fountain."

"What is this place?"

"This?" Otter sounded genuinely surprised. "It's the great city of Vern-Delnitz."

"Is it real?" she asked.

"Excuse me?"

"Just answer me," said Amy to the empty air.

"It's real, Amy. Of course it's real."

Amy started to walk away. The otter began to shout, then remembered that speaking through her mind it wasn't constrained by petty distances, or indeed a body. She chose a few random keys out and took a look through the tags. "You wouldn't happen to have a keyring on you?" she asked the town square. The empty air didn't respond for a good while.

"Oh, wait. You can't see me shaking my head nowadays. No, sorry, I don't," replied the disembodied voice a little way behind. A few years ago the city council decided to scale back and use soluble audio nano-bots only. This meant no more 'augmented' ads, thankfully, but also relegated the adorable otter guide somewhat. To the otter, the lack of a visible body made life pretty uncomfortable.

She chose a pair of bronze double doors, identical to all the others, and looked around for a keyhole. There was one, and this door was just as locked as all the others seemed.

"So then, are these locks normal? Can I use keys on them?" asked Amy. She used her good arm to carefully arrange her full collection of keys on the ornate cobbles. Her other one she didn't want to think about. That numbness was well past the point of no return.

"Usually tourists are troubled by my presence the first time I speak to them. Please, if you'd prefer to be alone, let me know."

"I'm just going with it today," replied Amy, "it's been a difficult afternoon, you know?" She touched the cool bronze of the doors, stared at the dragon motifs.

"You're re-thinking the medical aid. I'm re-thinking it too. The fact I can speak to you at all shows you're head's similar to the Kavaldish, but in the case of medicine the differences might do more harm than good." Amy thought of having a rant about the privacy of her head, and reckoned her mind-reading guide got the gist of what her beliefs on the matter boiled down to without her ever saying a word.

"So, keys it is, then, as expected. First step is to get back to a hospital somewhere," she said. "Then I need the police. The real police." The door before her was similar in style to the temple-bank. Simple, elegant, and tinged with the violet light of an eternal sunset. Trying to make all the light pass through rose-tinted glasses when you're hurt is tiring. Having the rose-tinted light physically thrust upon you, Amy realized now, is probably worse. She could've really done with some muted greys to reflect the situation.

'End' she wasn't going to use. Otter was grateful. A few other meaningless keys that had no double-meanings were likewise discounted when she found they did nothing. An 'X' key could do something horrid like produce her old boyfriend from the other side of the door. She picked up 'Y' and her mind quickly deteriorated in trying to find the meaning of it all: life, death, the keys, Kavaldish. The otter resounded her firm 'no' on that one and tried to reroute her thoughts away from questions. '5' and 'print screen' were both removed, and the 'K' key made a nice sub-group with 'tab' as potential food sources. That left the key with a question mark, and the car key. Question mark one first. It grated into place.

"Amy, you weren't taken apart and put back together when you used these doorways, were you? Did you have any lost time?" She turned away from the lock, and gazed toward the distant statue. Her tentative new guide seemed somewhat concerned. Its ears would be very much flattened if it had access to the virtual display at this point. She hadn't thought about that.

"Um, I didn't think so," said Amy, turning back towards the distant statue, and then back to wherever she imagined the voice was coming from. "That would be pretty crappy wouldn't it?"

"It wouldn't be good." Otter wasn't about to worry her about that too much.

"You know, it's just occurred to me you could be a really well put-together hallucination. A nagging one at that, like my friends had," she said.

"Amy, I assure you that blood loss may be bad, but it doesn't do what I do quite this vividly I don't imagine."

"No, I hope not," replied Amy. There were hundreds of doubts she didn't have time to think through and instead turned the question mark key into the lock and pulled. It opened into a small room.

"Put your hand through, then pull it out again, if you could," asked the otter. She did as it said. Her arm felt hot on the other side. After this Otter seemed somewhat satisfied that she wasn't being deconstructed and grumbled quite a bit about how 'bloody good the wormhole technology is for a race that hasn't even heard of Kavaldish runic'. It gave a small squeal when she looked at where the mahogany door frame blended nauseatingly into reconstituted boards on the other side. The room beyond the bronze door was quite plain, and illuminated its contents with the same halogen lamps and white paint used the world over for filing and archiving. On rows of stainless steel moveable bookshelves were cardboard boxes, arranged by date and season, each stamped with a year, the first starting at 1950. In boxes, binders. In binders, all information you could ever want to know. Makes, models, disqualifications, points, commentators, photos, rules were all there to see. On her keyboard the question mark key bringing up the help menu had also been F1. Amy was glad she left the door ajar. When she stepped into the filing room the heat suddenly, cloyingly returned. She retreated back into the purple-shaded market square of Otter's World.

"Formula 1," she explained bitterly "a form of racing. This key answers any questions you could have about it."

"Ah. Seems a little archaic to me," replied Otter. "And not very useful either."

"No, except for maybe a pub quiz, and even then you'd be cheating."

"Well that's a shame. It's always sad to see good wormhole work go to waste."

"I'm afraid that's just the way it is" she said.

"Well, have you really tried it properly? Put your back into opening these doors to the places you want them to go? Read the manual, Amy? Judging from your own thoughts 'enter' would have locked onto a different destination if you had a different screensaver." The otter was very pleased with itself. 'Locked onto' had been its first accidental English key-based pun. "If you swapped your screensaver for a different photo it might take you to a different realm, or the closest thing to what that photo shows."

"I'd happily give that a go if you had a spare computer, and if my friends who made these keys were here." The otter conceded that besides a museum, and the server banks running Otter's programming, such hardware would be challenging to get a hold of. She tried the F1 question mark key again instead, and a bit like last time with the door-full of air focused her thoughts on the filing cabinets. She imagined she could re-interpret "F1". It was part of the function keys. Function 1 was 'help', or 'query'. She concentrated on the word help. She meditated for a moment about the nature of function keys, then twisted through with her good hand. It opened. She slammed it shut again and felt a stab of pain through her dripping shoulder.

"You did seem to put your back into it that time. I was hoping that might do it."

"Trouble is, with something like an F1 query key there's no room for other interpretations. It says F1, so it gives me the only thing the F1 bit could possibly mean in regular old English." Otter nodded sullenly even though she wouldn't see it. Amy decided to try another key before the car fob. The car key had to be left for last, because either things were going to go a long way one way, or a long way the other when she did. The K. She hadn't used that yet. Amy imagined a chocolate torte. The exact chocolate torte that her mother liked to make on lazy Sunday afternoons after gardening. The key fit. She opened the door with the K-key to the sound of distant Italian, and a sudden familiar heat that was beginning to resurface. She walked through it all with her eyes closed and was hit by the smell of fresh pastry. Sugar, almonds. Amy blinked and frowned at the warehouse stacked high with treats. No, her chocolate torte remained as elusive as ever. She bled enough on the floor to warrant a reprimand for the bakery from a health inspector and shut the door behind her with a foot whilst cradling a pear tart.

"Nope. That plan's bust." The blazing heat she'd felt since this morning evaporated into oblivion in the cool sunset of Otter's world. Ending up in an Italian warehouse was hardly going to help three people in a hospital basement at the end of the day, if they were even still there. "I don't think we're going to solve it by being Zen."

"Damn. Zen usually works. You know, if those keys were mine, I'd be livid by now." Otter shook his tail and frowned in vain. It was premium animation to waste without visual nano-bots.

"Mhm, I am quite livid." Amy nodded in agreement behind half a pear tart.

"At least you got cake."

"Mmm, Sorry." Amy made a series of floating gestures with the tart to excuse herself for talking with her mouth full. "It's a tart, not a cake. Big difference."

"Oh."

"Helps keep your mind off the blood loss and the melancholy, you know. But not quite as well as Cajun chicken sadly." Otter found this remark a little strange even with his significant new insight into the human psyche. As an A.I inhabiting an amphibious statue he'd never tried chicken, or a tartlet, or even a boring Victoria sponge. Troubling. Still, he did better than Ichor.

"Well, if Zen-like control is out, I'm just going to have to do some voodoo prediction," said Amy crumpling the tartlet tin. She missed a fancy bin by a few feet but Otter let it slide. "First prediction is that there aren't any real meanings for F9, so it won't interfere." She checked the car fob and clicked the button to extend the manual key from its hiding place. On one side the word F9 was printed in block lettering. On the other were triangles and lines that looked almost like part of a Kavaldish rune. "The second is that I haven't misunderstood how this works." Amy took the car fob and turned it in the door of a timeless city. She gave a wave to the empty square. She wasn't sure if F9 was the key for 'rewind' or 'fast-forward'. After all, the symbols on her computer for both were exactly the same – two triangles, just that one was the mirror opposite of the other. She opened it with some considerable surprise. The room on the other side was stopped in time, motionless.

"Hang on, Amy wait fo-"

Otter's mind at the time and afterwards was distracted. That would be the excuse he'd tell himself in the coming pseudo-days as the Sun imperceptibly moved a few real-time nano-seconds in his universe. He'd wander the city alone for a while afterwards to think, would go as far as he could get from his computer banks. He later relegated himself to the few static cameras operational around the city. The audio nano-bots that made up their link were deconstructed in that moment and boiled away into a thin stream as Amy passed through the function nine door. He lost the signal. Otter didn't have a physical body to shut the door after it was opened, or to clean up the aluminium tartlet tin, so he just stared through the portal from his main position on the log for a while. The portal slowly lost some of its power and collapsed, still motionless and in freeze-frame on the other side. When it came to the tartlet tin he wasn't sure he wanted to get rid of it, so he didn't let it bother him. More than anything he was disgusted that reconstruction transmission portals were still legal anywhere.

***

"Do you know the way to the safe house on Charing Cross road?"

The man behind the wheel nodded in agreement and managed to glance reassuringly at his backseat driver.

"In that case slow down and let us out here. That would be perfect," said Schofield. One meaty paw held onto the back of the driver's chair for support and he took a moment to reassure the team there would be someone to meet them for a handover at the bookstore behemoth in Charing Cross. The van slowed and put on its hazard lights a few hundred feet past Knightsbridge station. Someone in the boot groaned. Schofield climbed out of the van and, remembering something, reached back for his guitar case. Mr. Raynes hopped out the other side and waved the van and their three hostages a terse goodbye. It was a bustling day on Brompton Road. Every day is.

"They police are bringing in people in from as far as Kent to start their own terror hunt, you know," said Schofield glancing through a news app as they skulked towards Harrods. "And it's barely one o'clock."

"They didn't tell you that was their plan?" asked Raynes. He didn't remember where Kent was, but that hardly mattered. His Englishman didn't answer, just continued to look pissed off.

"I was promised half a day to sort this out, at least," said Schofield. "But you saw the reporter vans. You can't win." Schofield dodged a couple with a stroller and weaved through the crowd.

"Police won't find her easily if we can't," said Raynes. "I guarantee you that much." They walked in silence for a while down Brompton road, past tourists, past prams and shoppers caught up in the gridlock from South Kensington. The cars barely moved, the black cabs did u-turns and ejected their passengers saying this is as close as they'd get to Harrods. The American was first to spot the store that Schofield had told him about in the car and pointed at a maelstrom of electronic paraphernalia that made up a hardware storefront a few intersections further down. "The place is still in business," he said.

"Good. They'll have most of the supplies we need. If not there, I know another place, but it's a longer walk."

It was one thing to use a 'shift' key to teleport down a hospital corridor and quite another to figure out a pattern behind how it worked. They'd need a few hardware supplies for an experiment, or a series of experiments if it went well. Why something impossible was happening was foremost priority. Then, once that was done they might be able to find Amy Packard. A golden Ferrari blasted its exhaust past them as they crossed the street towards Harrods'. Not to be outdone by a mere Ferrari, Brompton Road erupted into horns. While Schofield struggled to find a good mnemonic for an offending licence plate, Raynes took the opportunity to whisper 'fuck' as loud as he dared into his phone.

"What is it?"

"I just got a text from Navari at the embassy," said Raynes. He held it up for Schofield, showed him the list of messages and missed calls. They stopped in the sidewalk and leaned against a shopfront display. It was going to complicate experimentation.

"Oh. Do you have a say in this? I'm guessing not," said Schofield.

"Not usually, no."

"Then you shouldn't be showing me that, should you," said Schofield slowly. Raynes had shown him orders to return home, back to Embassy with the keys, or with the hostages if possible. He looked out over the distance westwards towards South Kensington, the electronics further down shop, the great edifice of Harrod's towering above it all amidst the snake of brake lights and two-lane thick stagnant traffic.

"No, I shouldn't be sharing what I just shared," said Raynes "but I'm feeling the spirit of collaboration today."

"It's a dilemma. We should talk about this without-", Schofield patted the phone in his pocket "-without this."

"True."

"Follow me. We'll go indoors." Schofield dragged him out of the crowds and into the cool elevator music of Harrod's, far past the rotating doors and the greeting staff and onto the marble beyond where the perfume and beauty section starts and feels like it'll never end. Great. Schofield wondered how many others like Raynes might be getting texts related to this series of incidents, and how many might get an order to start looking for them soon. Not to do anything violent, to be sure. Just to find them, and bring the American back to the Embassy to answer what the hell was going on. He marched them to a deserted corner near the specialty cosmetics and eyeliner.

"Okay. Show me the text again, properly this time. Let me think. What do you want to do about it?" Schofield heaved his guitar case onto a glass display case and wiped the sweat from his glasses. He read it again, unlocked the case and opened it a crack. The gap proved just wide enough to slide all five phones they owned inside amongst disassembled pieces of sniper rifle. They could talk in peace. Schofield learned quickly that the microphones on most phones listened and recorded people like him. The regular public probably less but himself and Raynes were special interest right now.

"How long does Navari give you to respond? Do they get worried if you don't answer before half an hour?"

"Up to an hour we should be fine, it's not unusual. Beyond that it'll be difficult to explain why I'm missing calls."

"They'll phone me too to ask for you," said Schofield. "How much do Virginia and people at the Embassy know? Did Navari know about the keys?"

"I don't know." They could have re-enabled the hospital camera feed when we used that key," Raynes listed, "or have our cell audio. I don't know, it's hard to tell. Maybe they noticed we didn't have our phones on us, that's another possibility, or maybe it's because they think it's out of our hands now and they want me back."

"They know the keys exist, right?"

"They know something's wrong, and they know there was debris from the explosion. Someone from the van could've told them the debris were keys. Maybe Mark."

"You didn't tell them?"

"No."

"What if you report in like expected?"

"Then that's it. I'll be put on the first charter flight to New York without warning. See you in two weeks for coffee if I'm lucky."

"And you got this text now, right? It came to you now, on the street."

"Just now. They set for me to go to the Embassy first, then City Airport."

"Do they want you to take the keys and run? That's the implication, isn't it?" The Englishman stared.

"Yeah, maybe, but hard to tell," said Raynes. He tapped at a glass cabinet of cosmetics absently. On the other side of the display forty types of mascara shook when he did. No, people in the darkened rooms of Virginia couldn't have the keys. He pointed to the case.

"Are we keeping the phones in there?" asked Raynes

"I think so. That depends on if you want to continue."

"I do. I'm assuming that's not a guitar?"

"It's not."

"I can ignore the message for now. I could argue that I didn't know the extent of the losses from the hack."

"It's not very likely," said Schofield.

"I'll play dumb."

"They'll come looking for us, and it's still a bad excuse," replied Schofield.

"It is."

"So, shall we continue?" Schofield hefted the case which clanked with the sound of shifting phones and brushed past sales assistants to head back outside. Five phones all with pinpoint GPS tracking weren't healthy and at some point they'd have to ditch them. For now keeping the GPS on was less suspicious. And one of those five wasn't a normal mobile.

They walked past Harrods, stopped a little ways beyond and had Raynes delve into the fading hardware and electronics paradise for the necessary supplies. The plan was the same. Schofield noticed the store's two-tone pinstripe awning was sun-bleached enough to go one-tone.

"Fine thanks" whispered the American to no-one in particular as he entered the store. It was a force of habit. He forgot he was in England where store clerks don't ask 'hihowareyoudoingtodaysir'. Red wool carpet, plastic DVD players, SIM cards sold by the kilo? He was in the right place. The friendly sign outside stating 'Keys cu ere' was equally reassuring.

Most people are put off by being in small shops alone as Raynes was now. You'd typically follow a ritual, glance with interest at a pair of headphones, then struggle to put them back on the rack. A few nearby SIM cards might inevitably fall off their display in the fray. You move to the aisle next door and give a frown at the weight and quality of the ferric cassette tapes. Raynes didn't. Spotting what he needed, he took three and marched to the counter. He didn't even give thought to the different designs he could buy, their security features on the packaging, or consider whether he was overpaying by a pound-fifty. Three padlocks were picked at random and ended up heaped in their hard plastic shells on the counter.

"Anything else?" asked a tired clerk. He wasn't actually tired, but tried his best.

"Yeah, actually. I'll need these cut." Raynes produced a 'shift' and a small 'spacebar'. The keys were taken and store clerk turned on the lathe with some hatred while Raynes dug his wallet out from past his box of ammo and paid, then glanced outside while the shop clerk began making him the copies. Schofield had found a nice couple with a Labrador and was petting it on the street with satisfaction.

"...we've thought of getting a dog for a while now. My daughters especially. They're mad for animals. Is she a cross? Oh, a lab-poodle mix, I see..." Schofield had already mentioned his past pets in passing, and was just about to ask whether the myths about lab mixes malting were true. He couldn't have his home covered in dog hair. Raynes emerged with his padlocks, cut keys, and few other essentials he'd found last-minute.

"Ah, here's my colleague, Paul. We'll have to run now, I'm afraid. We're late. She's absolutely lovely, though. What a wonderful dog." Schofield said his goodbyes.

"That's everything?" he asked.

"I bought the padlocks and all," replied Raynes.

"They took their time cutting," said Schofield. His colleague agreed that he'd had more than enough of that guy sawing away at the lathe. The two agents managed to make some progress through the street and followed the stationary traffic to come up almost back at Exhibition road and the roadblock where they started. They'd arrived. It would be difficult to miss a church this size, really. It would do for a makeshift laboratory. Raynes was much faster up the stairs to the main doors and took a peek inside.

"I think it's all quiet in there," he said.

"Oh, thank God," came the wheezing reply from a few steps below. Schofield struggled up the church steps of the enormous Brompton Oratory with the significant weight of a good few kilos of hard plastic guitar case, and five stuffed phones. Recovery from the trauma of propping up Agent Raynes, running through corridors and petting doggos was going to take some time. They found themselves in luck. No choral practices, or organ recitals. No masses. The Brompton Oratory was more or less deserted. Burning incense wafted through the air and decided mid-breath to turn to wood musk.

"This way, I reckon," said Schofield. The case clanked as he walked, and the rifle inside ground against the five phones within. It was not for the first time for him to be moving heavy weaponry and crime scene evidence down the aisle of a religious building. There'd be few, if any cameras on here and few, if any, people seeing strange things during private key experimentation. Unfortunately, it did occur to him that witnesses of one wrong 'shift' might suddenly make the Brompton Oratory the site of a miracle. Statues of disapproving saints lined the walls. How very dare you, they might've muttered. These sculptures and paintings are a masterpiece. How dare you bring your chaos here?

The two climbed the stairs past the vestry and found a secluded balcony on the upper levels with a convenient door to a miscellaneous store cupboard. There were no pews. The oaken floor and the cold walls of the upper levels were the only thing to sit and lean against.

"Can you stand lookout?" asked Raynes whilst struggling to cut his way to his padlocks through clamshell packaging with a Swiss Army knife. As public buildings went this was the most private and quiet place either could think of with the exception of anomalies like the financial regulation archives in the Bank of England library. Such archives were never used, and are considered poisonous to any banker worth their salt.

"Sure," said Schofield. "We'll speed through this. Give me some of the keys while you finish with cutting those open." He took some keys, stood at the balcony with them laid out on the banister and set about methodically checking for onlookers. There weren't any that he could see, though the naves below remained obscured. There was no-one from the U.S embassy slamming open the doors. He sorted keys into two piles. For the ones in his left pile he could have an educated guess as to what they were for. For those on the right he either had no idea, or thought whatever power they held would be useless.

Schofield turned to check on his colleague, who'd fished out the thing he'd bought last of all in the hardware store as a surprise. It had an ergonomic grip, titanium finish, and it was perfect. It lay next to Raynes, who'd sorted his keys out the same way into piles. They merged the two. 'Escape' went to the useful pile, as did 'I', 'spacebar' and a cracked plastic hotel key card with a QR code printed on its surface. Block lettering stated that it was a 'Control' key. Whether control was a hotel brand, or something else entirely they couldn't tell.

"I'll take the ones we don't need," said Raynes. "We're not letting DARPA or the MoD, or DSTL, or whoever else near this bullshit."

"I'm glad we're on the same page, Mr Raynes. Will you be using that?" Schofield pointed to the ergonomic grip of a pair of wire cutters.

"Oh yeah. I'm cutting as many of these as I can."

"Revenge for making you feel ill?"

Raynes ignored him and set about cutting the key pile they didn't want into pieces. It was a satisfying job. Slices of nickel-plated 'L' fell to the floor and was lost amongst the floorboards. He cut the tags too. The gold-coloured 'R' was destroyed next. Then 'P' and '@' felt the full force of wire-cutting technology. Schofield found some of the pieces and scattered the spent metal over the edge of the balcony to the church floor. He brushed a few remaining slices into his pockets to dispose of elsewhere.

"A lot of people would say destroying a resource like this is idiotic."

Raynes shrugged and kept clipping. "Some people don't know what they're up against, then." There were still direct orders on his phone to keep the keys and bring them back to the U.S. An ominous amount of secret service and bomb disposal was on its way to take away the monumental amount of ammunition at the first terror site in South Kensington. People were beginning to catch on. There were early rumours from Schofield's sources that a Singapore flight being hijacked over Germany somewhere. Raynes finished his cutting.

"What've we got left?" asked Schofield.

"These four, plus 'backspace', 'home' and 'mute', and the ones I had copied."

"The hour of experimental discovery approaches, Mr. Raynes. I'll try the copies first."

Schofield squinted to check that the teeth of both 'shifts' matched up and put the tag-less one to the test. He braced for the nausea and thought this time the morning biscuits would return on him for sure. The key wouldn't twist. Oh, thank Christ for that. He forced it, but it wouldn't turn. He shook his head.

"It won't go. At least you can't copy it." He gave the key to Raynes, who cut it.

"Try the normal one in a padlock," said the American, nodding at the real shift.

"What? No. Last time we both ended up on the floor. You needed five mints to get up. I've taken the first leap. It's your tur-."

"Fine. Something else. Keep quiet."

"I don't want us going to space on second thought, so those two are out. Cut 'em," said Schofield. Raynes did, reluctantly, and pieces of both 'spacebar' and 'backspace' keys fell to pieces. "That leaves us really with 'home', 'control' and 'escape'," he continued. "I think I can guess where a home key could teleport you. It's not a big risk. We could try that?"

"Home for you and home for me aren't the same. That could matter," asked Raynes.

"True. In that case let's not find out. We'd end up taking another flight to get back here if you open that. Where do you live, Oregon or somewhere?"

"Yeah," said Raynes struggling not to frown that Schofield knew that. "But you hold on to it. You're from around here. We'll test 'control' instead. It's not a real key anyway, it's a keycard."

It took them a moment to find out how to install a QR reader, and another to work out how to get the plastic 'control' key card to scan correctly on Raynes' phone once they pulled it out from amongst disassembled rifle. It brought them to a webpage painfully slowly. The webpage was a spreadsheet table. That was it. Four headings in bold. Name. Function. Type. Location. There was no web address, just a blank line. Raynes tried to scroll to the bottom of the table in vain and barely made a dent, then returned to the top. He whistled.

"Well?" asked Schofield looking over the balcony to the aisles below.

"And so it continues. It's a spreadsheet." He bent the key card and inspected it. It was just a regular card, cracked a little from the explosion, the kind like you might find at a hotel, or an office. All that was on it was the QR code, and of course the word 'control' hand-written on a corner in the same font as the tags and the rest. The first irrational rows of the spreadsheet were marked 'F' and a number under the 'name' column, from F1 to F12. Further down were just numbers, with a few eccentric entries thrown in. Below in the entries came letters, arranged neatly in QWERTY up to P.

Raynes read one at random. "Name - 'Q'. Function - moves user to location of the nearest queue containing three or more individuals. Type – transfer. Location – variable." He ignored the ones lower down and checked the list for 'shift'. "Name – 'shift'. "Function 'moves user horizontally'. Type – 'transfer instant'. Location – variable."

Raynes called the fat man from his railings. The man from the railings looked tired.

"There's no-one new at the Embassy, is there? Someone you've not mentioned who I'd not recognize stepping through the doors?"

"It'll be Hortez or Navari searching for us. They're the closest," replied Raynes. If they were coming for him with Hortez it didn't matter so much whether his phone was tapped or not. He'd be suspended for sure.

"So far there's only a few people early for mass and none look like Hortez," said Schofield. "Besides, I'd know Navari if I saw her."

Raynes didn't want to mention he'd received another text while he'd been browsing the Control List. It clarified details of the first text in ways he'd rather overlook, and mentioned Agent Hortez too. As for the people sending those messages, a number of them Raynes reckoned were getting eyestrain from staring at screens about him in dark meeting rooms and had to push themselves past the blurred vision. After all, sharp shadows and deep voices were the whole point of dark meeting rooms. Schofield sat down beside Raynes on the hardwood balcony floor.

"You've got dust on you everywhere from the railing," said Raynes pointing. "And you left imprints on the balcony." Schofield dusted off months of wispy debris and incense, and Raynes dusted off the part that fell on his own jacket. He showed Schofield the spreadsheet.

"Name – 'control'. Function – 'produces full list of functions'. Type – 'data'. Location – N/A. We were right on most of these, give or take." Raynes finished reading the entry. They sat in the balcony shadows for a while, exhausted. "Spacebar would've been useful," he said.

"What's the best out of what we've got left?"

"Escape's good. Some don't have entries like 'L'. They do nothing."

"What about 'mute'?"

"I'll cut it. It strips you of speech." Raynes had gotten pretty good at the wire cutters by now. His partner scrolled through the entries, and reached the section where the list repeated in French, then German, and so on. Both barely made a dent in it. There had to be dozens of language versions.

"Shame you can't edit this," said Schofield. Raynes had already tried it, and failed. You couldn't download it. Or change it. Screenshots came up blank. You couldn't find the webpage either.

"I've tried everything to copy it. It's got heavy protection." He kept slicing at the tag. 'Mu' fell to the floor.

"So the list controls what the definitions of the powers and the double-meanings are but doesn't actually give you control."

"Maybe. The type is 'data', most of the rest are 'transfer' You can't know either way, right? You can't change any data entry, so you can't test if it would make the keys have different powers. It could just be a list."

Raynes stood, looked over the balcony, and still saw nothing out of the ordinary. His partner meanwhile read a few entries they'd never found the keys for. Some of them were deadly. 'End' had to be cut if they ever found it. Somewhere right at the top was 'Escape'. Function – 'escapes doomed timelines to those with potential'. Type – 'transfer'. Location – 'variable'.

"I guess I'll try this, Mr. Raynes. Time to use one of your padlocks for a change. After all, doomed timelines sound damn invigorating."

The key shouldn't have fit the padlock but did anyway. It hurt his eyes to look at the lock barrel and his vision blurred whenever he tried to make sense of how the hell a key that size could fit there. Schofield twisted the 'Escape' and winced. Nothing overly dramatic happened. He stayed where he was, the key turned and the lock stayed closed. On the other hand, he now saw paving slabs through the loop of the lock where there should've been holy church floorboards. Even MI5 agents get vertigo sometimes, and this was one of the handful of moments. He held up the padlock closer and looked through the loop. Angling it showed the slabs were part of a pavement. The pavement was bordered by shops, a street, cars, and people mid-stride, motionless. On a hunch he took out his gun and put the barrel through the loop. Suddenly his revolver was snub-nosed when he looked at it from the side-on.

"Paul, pass me a mint, please?" One extra-strong one was dropped through the loop and clattered to the paving slabs on the other side. The Brompton Oratory was now down by one mint. "Can you see what I'm seeing looking from the other side too?" he asked.

"Yeah. It's a street. And I can see your car, that's your registration. That and the siren's a giveaway" said Raynes

Schofield turned with padlock in hand like a compass to face the same direction as his partner and stared through the loop of the padlock towards the vestry staircase. Raynes was right. When you turned the panoramic street-view this way you could see their car, the street, and the marble walls and staircase of Brompton Oratory in the background surrounding the padlock loop where they really shouldn't be. All perfectly still.

"It's Fulham Road. That's a frame from this morning."

"Yep."

"If it's really from this morning, then it won't matter what Miss Packard is doing." Schofield turned away from the lock. "We know where she's been, don't we?"

Schofield removed the 'Escape' key. The street-view portal vanished. He fumbled, dropped the padlock and muffled his swearing for the sake of the devoted downstairs. The loop of metal began to sizzle into the floorboards. Picking it up with a handkerchief he noticed it had burned a nice black 'C' into the oak. He wrapped it, and opened the door with the key instead. Luckily Mr. Raynes had the foresight to bring their guitar case full of rifle and phones with them.

On the other side of the door was Fulham Road. They could see it, the same view, just bigger. The two agents walked through and stepped on a mint carelessly left outside the door to a French bakery. The 'Escape' key went back into one pocket, and the land beyond unfroze. They were just in time to watch a speeding hybrid get obliterated by a garbage truck at the intersection. Plastic shards ricoched through the crowd and obliterated the better part of a bus stop. Someone screamed when the mess of police siren clipped their shoulder, then stopped screaming as they slapped the concrete. The hybrid flipped and rolled through the display of a corner coffee shop, and laid to rest seeping and bloodied between a scarcely touched latte and a ruined display of organic java that spilled. The front of the truck it hit lay dying in the middle of the crossroads. Amidst naked engine and airbags its horn still blared. And if you were listening to the universe it might speak to you. Let the games begin. You've used the keys now, Schofield. Oh yes, you've found out what they do, but you should've known there can be only one copy, shouldn't you? There can be only one Schofield, and only one Raynes. You're lucky. You've escaped a doomed timeline, gone back to when things weren't hopeless. Even if you don't know it, you've escaped a world that collapses into nothing. And you're lucky it's not you choking in that car. That's very lucky indeed.

"Schofield?"

"Yes, Paul."

Can you hear them? Can you hear them choking?

"Was that us?"