They retraced their way through a few rooms, with one trio of soldiers in front and one behind. Presently they came to a doorway they hadn’t been through before, blocked by a knee-high morass of books.

“If any of your redshirts feel like helping us clear the way …” Jill said.

“Chuck?” Michelle said to one. He tried kicking in the door without success – it was wedged between so many books that he’d have to snap it in half, and it was thick oak – then instead aimed his weapon, an automatic shotgun, and shot out the latch and hinges. From there, he just had to lean against it, and his weight levered enough books out of the way to make an opening. What had taken Roger long minutes was accomplished in seconds.

They trooped into the next room, which was much larger than the previous one. It was double-storey and had a number of doors; overhead a catwalk was suspended by steel cables, but there were no obvious stairs or ladders or any other way to reach it. The walls were lined with suits of armour. Where a normal mansion might have had stone plinths, these were instead set atop piles of the largest books, some of which weren’t perfectly level, making the armour somewhat lopsided.

“What’s that insignia?” Jill asked, peering at one soldier’s shoulder. “Xpros?”

“Chipros,” Aaron said. “Greek letter, cos it’s cool. We’re a private security outfit.”

“Specialising in retrievals,” Roger said. “And not usually of books.”

Aaron raised his eyebrows. “You’ve heard of us? Not an ex-member, are you?”

“I don’t need money that badly,” Roger said acidly.

“Meaning, you were on the other side?” Aaron guessed. Roger said nothing. “Hey, it’s cool. We don’t hold grudges; I only care about the job at hand. You don’t get between me and that book, we don’t have a problem.”

“Sure,” he said, thinking of his sister. “Only worry about the book.”

“So what’s your story, Milady?” Jill asked Michelle. “Bored enough to go adventuring for a book that might not even be real, rich enough to hire a troop of mercenaries, persistent enough that you might actually manage it … you must be a princess?”

“Heiress,” Michelle corrected, looking surprised that Jill had guessed so well but trying not to admit it. “What are you? You’re awfully calm for someone who’s just had a gun pointed at her head.”

“Just a sightseer. Truth be told, I’ve had plenty of guns held on me before. Not that yours aren’t impressive,” she assured her, “I’m just jaded.”

“How are you still alive, then, if you go around annoying people like my crew?”

Jill shrugged. “I have good instincts for not being quite annoying enough to be worth murdering. It’s a delicate balancing act. Through here, please,” she added to Aaron, who motioned to Chuck again to shoot out the latch and hinges.

They had a moment’s impression of a huge, open room full of light and dark patches and obscuring interior walls, before there was a noise like a combination of a snake’s hissing, a lion’s roar, and a motorcycle’s engine; the soldier leapt backwards and slipped and fell on his butt, and a massive flashing green-grey thing crashed into where he’d just been standing, throwing splinters from the doorframe, then bounced off and around behind a wall, spraying bits of cover and paper in its wake. There was a strong smell of burning diesel.

“… What the heck was that,” Michelle said.

The soldiers exchanged glances.

“Am I crazy,” said Roger, “or was that a komodo dragon riding a motorbike?”

“You’re crazy,” Michelle said. “Komodo dragons don’t ride motorbikes. They don’t even have opposable thumbs.”

“Normally I’d see your point,” he said, “but I’m pretty sure it had teeth, scales, and a tail. And look, there are skid marks on some of the books there.”

“It wasn’t a komodo dragon on a motorbike,” she said.

“Hey,” said one soldier, bending down to pick a piece of paper off the ground. “I think this was stuck to the wall and fell off.”

He held it out. It was a handwritten note: Warning – gatorcar ahead – do not enter! – SW

“Gatorcar,” Michelle said, rubbing her temple.

“Well,” Roger said, “that’s pretty close to a –”

“Would you kindly shut up about the komodo dragon and the stupid motorbike,” she said wearily. “Aaron, can you kill it, whatever it is?”

“I guess. I mean, neither alligators nor cars are bulletproof,” he said, shrugging.

“Um, are you sure about this?” Roger asked. “Because I’m pretty sure some of these walls must be load-bearing, but I don’t know which, so spraying high-powered ammunition at a very fast target maybe isn’t the best idea?”

“Can we just go around, then?” Michelle asked. “This isn’t a video game; surely there’s more than one way from point A to B.”

Jill flipped through the book, forward and back, taking in the map as it flashed by twice. “I can see two alternate routes that aren’t too far out of our way. One goes via the elevators –”

“NO!” everyone else shouted.

“– and while the other also involves changing floors, there are stairs that way, then a boiler room, then some more stairs. I’m sure you’re all wondering why anyone would use a boiler room as a thoroughfare, but unfortunately I have no wisdom to share on that point.”

“No-one was wondering that,” Michelle said. Aaron nodded. “Which way?”

“Through here.”

She picked a door that opened up to what could have been a very nice ballroom if it weren’t knee-deep in books. They were at the top of a grand staircase leading down to a wide space with dozens of outgoing doors. There was a crystal sculpture of a woman in a crinoline, and a golden chandelier hung from the ceiling. Jill double-checked the book, then made for a door out to one side. It led to a stairwell leading down four floors, bare concrete lit by fluorescent bar lamps, some flickering, and with only a few scattered books; overall, it felt more like an industrial fire escape than a part of the Library. Their footsteps echoed as they descended.

“This had better be worth it,” Michelle grumbled.

“If I had told you fifteen minutes ago that it wouldn’t be, would you have left us alone?” Jill replied.

“.”

The temperature steadily increased as they went. Finally they reached a fancy wooden door that looked bizarrely out of place at the bottom of the industrial chic stairwell. Jill walked forward, took the handle, then yelped and jumped backward, sucking her hand.

“Jill!” Roger cried, darting forward to catch her in case she slipped. The soldiers raised their weapons, uncertain what they were supposed to be aiming at. “Are you alright? What happened?”

“It’s nothing,” she said, holding her hand out to look. Her palm had a bright red line just below the fingers, where she’d touched the handle. “Just a burn. But that’s not supposed to be possible. I don’t understand.” She traced it wonderingly with the fingers of her other hand, like she’d never seen anything like a burn before.

Aaron pushed past them and rapped the door handle with the back of his hand. “Yep, this is hot.”

“And touching hot things burns you,” Michelle said from a few steps up. “I don’t see what’s so impossible about that.” Jill said nothing. “Can’t someone with gloves open it, then?” Michelle added.

“Yes,” Jill said, still staring at her hand, “but why do you imagine it’s burning hot, if not because the other side is and the metal handle’s conducting the heat? And if this side is too hot to touch, how bad do you think the other side is?”

“What do you propose, then?”

Jill licked the burn again. “I’m not going through there.”

“You’re the guide.”

“The map doesn’t mark down which rooms are or aren’t on fire. I don’t think any maps do that.”

“If it’s on fire, where’s the smoke?”

“On the other side, where all the fire is, I expect.”

“This is ridiculous,” Michelle said. “Chuck, open the door.”

“If there is a fire there and you open the door,” Jill said, “it’ll flare out and roast us all, and suck the air out of our lungs and pump carbon monoxide in its place.”

“How do you know so much about fires?” Roger asked.

“Um, physics?”

“Open it a crack, then,” Michelle said, rolling her eyes.

“Okay,” Roger said, hastily pulling Jill up to the next landing, “just let us back up a bit … don’t want us civilians getting in your way …”

Chuck nervously edged forward, placed one boot so as to block the door from opening more than a crack, set his black Kevlar glove on the door handle, twisted, and pulled it slightly ajar.

There came a jet of silvery gas, and he shoved the door shut with his shoulder; everyone else jumped back in alarm, and Jill skidded on a book and crashed into Roger, who caught her and kept his own feet. The gas quickly dissipated, leaving the air in the stairwell warmer and moister.

“… Steam,” Michelle said. “Not smoke. Open it properly.”

Chuck moved forward again and opened the door fully, letting another cloud of steam through until the air pressure equalised. There was a flight of wrought iron steps down into a room full of great cylindrical pistons and boilers, all of it flooded. Around the machines, small bubbles boiled up through the water. A grate on the ceiling constantly poured in fresh water.

“So, just to be sure, this is the boiler room you mentioned, right?” Michelle asked. “Whoever built this place wanted a visual pun more than to not be completely retarded?”

“Yes. Yes they did.”

Michelle bent down and splashed a finger against the water, then tossed a book in; it quickly dissolved into a mess of pulp and ink. “There’s no way to wade through this; we’d be cooked alive. Is there some way to turn the boilers off, or a drainage system we can open to clear it out?”

“You’re seriously overestimating the detail in my map.”

Michelle harrumphed. “This, the gatorcar, or the elevators … gatorcar. Definitely the gatorcar.”

They turned and climbed back upstairs.

“So I probably should have asked this earlier,” Roger said as they walked, “kind of distracted, can’t really think why … but do you happen to remember the way out of here?”

Aaron snorted darkly. “I swear this place changes around when you’re not looking,” he said.

“That’s because you’re an idiot,” Michelle explained. “If it did that, it’d be impossible make a map of it. Not unless the map also moved around, so unless Glasses here is actually carrying a smart phone wrapped in a wad of paper as a disguise …”

“It’s a testament to how weird some of the people around here are that that isn’t actually all that farfetched,” Jill said. “I only wish I’d had the presence of mind. Or a smart phone.”

They made it back to the room before the gatorcar. Aaron motioned his soldiers forward. “Alright,” he said, “everyone shut up: we’ve got work to do. This door is a choke point. Men, ready your grenades. We’ll throw on my count, then rush in with a staggered formation …”

Roger tuned him out and looked around. The catwalk overhead drew his attention – he was fairly sure neither alligators could climb – but he still couldn’t see any way to reach it. There were plenty of random objects lying around, but nothing like a grapnel or a rope. Instead, he cleared out a patch of ground, exposing navy blue carpet, then began stacking books, making sure to lay them all flat so he could make a tower. It turned out to be easier said than done: there were some very large books, but most were smaller, so he had to lay several down side-by-side to form the base, and they weren’t all of equal thickness, so it wasn’t perfectly level. After a few layers, the tower began to wobble, so he had to go back and make a thicker base to compensate.

The crew wasn’t having much luck either. The grenades had only managed to make the gatorcar angrier than usual, so now it was pulling nonstop wheelies in the next room and bouncing off the walls, moving too fast for anyone to get more than a glancing hit to ping off its chassis. Michelle’s palm was glued to her face; Jill sat cross-legged with an expression of condescending amusement like that of someone watching a funny cat video. The soldiers bunched up at the doorway, unwilling to enter the room but unable to get a decent position from outside.

“This is stupid,” Michelle was repeating over and over, her voice largely drowned out by the bark of gunfire, “this is so stupid …”

Roger finally got his book tower as tall as himself. Jill turned to watch with detached interest as he scuffled up the side, careful not to knock it over, climbed on top, stood to gauge the distance, crouched, sprang, and grabbed the catwalk above with a clang. It swung in space, but the cables held, and he managed to pull himself up. He lay there panting, wishing he exercised more often.

“Hey, stop shooting!” Michelle said to Aaron, then, sweetly, “Hey, nice thinking, Roger. Do you see a ladder up there?”

The catwalk was made of steel plates loosely wired together, so they could see a person moving along it from below but not items resting on a plate. From Roger’s position, he could see that there were a few more books lying around, and the usual assortment of random items, including a butterfly knife this time. He quietly pocketed the knife. “Nope, nothing. You’ll have to climb up.”

Michelle looked at the book pile doubtfully. The recoil from his jump had knocked it askew, and it didn’t look like it’d survive a second one. Even if it did, she was shorter than him, and he’d barely made it. They’d have to build the pile up higher and stronger, and then she’d need a boost or a second pile to even get onto it without toppling it, and then she wasn’t strong enough to do a pullup. “Isn’t there anything?”

“The more you ask, the more the answer will stay the same.”

Michelle thought. “Go ahead and look for something, then. Your friend stays here with us. Aaron, forget the gatorcar and help make a platform.”

“You do realise we’re going to the same place as you, don’t you?” Jill asked, arching her back in a stretch. “You don’t actually need to threaten us? We’d probably ask to tag along anyway; I mean, I wouldn’t fancy clearing out any more doorways by hand.”

Roger looked at her, unwilling to abandon her, but she seemed bizarrely relaxed considering she was being held at gunpoint. “If you’re sure. Does the map say anything?”

She flipped through her map book, not really expecting anything. “This and the third dimension aren’t on speaking terms. It has other floors, but they’re rendered side-by-side and the overhang isn’t marked at all. The vault’s close, though.”

“Don’t keep us waiting,” Michelle said.

Roger made his way along the catwalk. It had a T intersection in the middle of the room, the three paths leading to what seemed to be human-sized cat flaps in their respective walls. He went along into the gatorcar room.

The catwalk split in two to follow the walls, which were lined with extra-high bookshelves, like how normal libraries have rolling ladders to access the top shelves. There was a ladder leading to the ground at one point. From up here, he could get a better look at the gatorcar.

From ground level, it was a blur of biomechanical fury that moved too fast for much observation, but from a safe vantage, he could see that it was a surprisingly elegant fusion of animal and machine. Its head, back, and tail were ridged and scaly like an alligator’s, but its legs had been replaced with large, narrow tyres like a racecar, connected to the front and rear quarters of a bright red chassis. It had a pair of scarlet spoilers, and fore and rear lights that winked on and off, looking random and angry. Its sides were partly scales, partly metal plates, in an organic pattern that looked oddly similar to a normal animal’s markings. Along one side was a poison green decal reading WOO. The paint was chipped and pitted by grenade shrapnel and its repeated collisions with walls. The jaws snapped as it went along, spinning through the room.

I wish I could say this was the weirdest thing I’ve seen today. He continued along the catwalk. The gatorcar spotted him; it snarled and snapped at him, but couldn’t do anything to stop him passing. At the end of the room, the two halves of the catwalk rejoined and led to another cat flap.