The second door opened into a vaulted room, remarkable for being the first place they’d found that wasn’t full of books. It looked like some sort of shrine, with a long marble altar in the middle. Instead of the ubiquitous electrical cluster lights throughout the rest of the Library, there were stone pedestals on which sat hundreds of smokeless candles, as well as photos and flowers in vases. The ceiling was covered by a stained glass picture of a wasp; the walls were covered with off-white tiles that formed patterned mosaics of white and grey.

An ugly hunchbacked man with a monobrow wearing a green cassock stood by the altar, scowling. “This isn’t supposed to be here,” he growled.

“Excuse me?” Roger said as he approached. He looked around, taking in the jarring change of scenery.

“This room isn’t supposed to exist,” the hunchback repeated.

“… Because it’s not full of books?”

“Of course,” said the hunchback, and Roger couldn’t tell whether or not he was being sarcastic.

“I don’t know,” Jill said fatuously, “if you can have multi-faith worship rooms in an airport, the same in a library isn’t too out of place.”

The hunchback scowled at her, a nonverbal shut up.

As they spoke, Roger wandered over to a pedestal for a better look at the photos. A chill went down his spine.

“Why are these here?” he said, very slowly and deliberately.

“I just said I don’t know,” the hunchback repeated, annoyed.

“Not the room. These photos. Who put them here? Are they yours?”

“Remember the part about me not knowing?”

“What’s so special about them?” Jill asked Roger, walking over.

“These are all of my sister.”

There wasn’t much resemblance in a photo. She was shorter than him, partly because she was only fifteen, and had auburn hair she wore in a ponytail. She at least wore similar clothes, although her taste tended toward pink. The photos were mostly recent, but in a few she was just a toddler. She was doing all sorts of things: pushing a trolley in a supermarket, playing soccer, reading, eating cereal with milk, watching TV with two other kids whose faces weren’t in focus, and there was even one – to his immense disquiet – of her dozing in a bath.

“Who else has been here?” he demanded of the hunchback.

“Whoever built it,” he said sourly. “This room isn’t part of the original design. I’ve no idea who could have done that. With all the security, it should be impossible to expand the structure like this.”

Roger considered the possibility that he was lying, but he seemed too angry, like one would be after a vandal threw a rotting animal carcass into one’s front lawn. He also considered burning the photos, but on second thoughts, if whoever owned them came back, it’d be best if they didn’t know that anyone else had been there.

“Do you know about the Library?” Jill tried. “My name’s Jill, by the way.”

“Of course I know about it, but it’s here that’s important,” said the hunchback, ignoring the introduction. “It won’t help to talk about that.”

“Do you know who made it?” she asked. “Or why?”

He looked around balefully. “How many times do I have to say I don’t know?”

“I meant the Library.”

“The architect’s around here somewhere,” he said, waving his hand vaguely, as though trying to give directions but too lazy to remember. “She made it to have somewhere to play, although if you ask me she’s letting it go to waste. Your lot don’t know a good thing when you see it.”

“Well, mystery solved,” she said, deadpan. She glanced at Roger, who was pinching the bridge of his nose. “Thoughts?”

He let out a huff and straightened. “If she has a stalker here, that’s just one more reason to hurry up and find a way back home. Do you know the way out?” he asked the hunchback.

“There is no way out.”

“There’s a way in,” he insisted. “There must be a way out.”

“This is going nowhere,” said Jill.

“If you want to do something useful,” said the hunchback, “there’s an old lady wandering around somewhere. If you run into her, tell her to get over here. This could be a situation, and she’s the expert on this sort of thing.”

“I will,” Roger promised, “if I see her, but we don’t know where we are, so if you could point us in the right direction …”

The hunchback gave a grunt of exasperation. “There’s someone who’s been studying the history of this place long enough to know her lefts from her rights. She’s set up camp in one of the vaults nearby. Go pester her; she seemed lonely enough that you wouldn’t be annoying her.”

“Okay, thanks. Bye.” He and Jill turned and left. They made their way through the room with the pillars and vines and to the third door. “Ugh.”

“Are you upset about the fact that your little sister apparently has a stalker, or the random cryptic hermit going out of his way to be unhelpful?” she asked.

“Both, although I specifically meant the photos. Would you mind if we ran back and fetched her now? I’m starting to get worried about her.”

“I don’t think it’s a good idea to bring her here,” Jill said. “He said that place was set up recently, meaning whoever did it is probably nearby, and if they come back …”

Roger sighed. “I realised that while I was speaking. I just don’t like it.”

“We’ll be quick, then.”

The third door led to a small square room. Like all the others except the altar room, it was covered with books; this room was noticeably warmer, courtesy of a large electric heater under a glass table. On the table was a sheepskin rug, on which a Siamese cat was curled up; when Jill instinctively detoured to pat it, it glared at her until she gave up and she and Roger passed through the slatted door opposite.

The next room was full of desks with chairs like a high school classroom. The walls were covered with tapestries of what looked like boy bands, but with their names replaced by the unreadable script from before. Two vending machines stood in one corner. At the far end was a desktop on an ornate stone plinth. They made their way over, and Jill logged on.

“Does this one need a password too?” Roger asked.

“Nope. General access. The functionality is restricted, though. You know how normal libraries don’t have any software except the catalogue, so that kids don’t hog the computers to play games? Let me see … here’s a list of software. Ooh, network access … offline, drat … but I can see what subsystems are still running. Air filtration, water, power, vending machine resupply, something I can’t translate, reprints I think, fire suppression, silverfish control … security offline, self-diagnostics offline. Huh. And there’s a recent announcements page that hasn’t been updated in … eight hundred years.”

He made a mental note of all that. “A map?”

“So we’re just ignoring the eight hundred years thing?”

“Is that the weirdest thing you’ve seen in even the past fifteen minutes?” he asked. “I know it’s very mysterious and all, but I just want to get back to my sister.”

“Mm. Fine. I suppose I’ll come back after you leave, and poke around some more then. Anyway, this is it.” She opened a file, and a set of blueprints filled the screen, marked in squiggles. She began pointing places out to him. “We’re here; we came from here … which means we met way back somewhere around here, I think. The stalker shrine isn’t marked, so I assume the hermit was telling the truth when he said that it’s a recent addition. Either way, he said to get to the vaults, but – true to form – he didn’t say which, and we didn’t ask because we didn’t know it was ambiguous. This lists five, in these locations.” She pointed them out. “On top of that, this machine only has a map of the local area. There might be more vaults further away, but we’d have to go there in person and find more terminals to find out.”

“What sort of moron makes a map that only shows places close enough that you could just walk there directly?”

“The same kind that made those elevators. Give me a minute to find the best route. Hey, can you get me something from the vending machines?”

“Er,” he said, not sure how to go about that but unwilling to refuse her. He walked over. They were marked with the Arabic/Indian writing, as best he could tell, so he couldn’t read any of the packaging, but there were coloured drinks in glass bottles, what had to be chocolate bars in plastic wrappers, and something the size and shape of small cheeseburgers in completely cryptic honey-coloured paper. “It needs money.”

“Whack it with a book,” she suggested.

“I don’t like stealing,” he said.

“The owner hasn’t been around for eight hundred years. No jury would convict.”

He found the largest book in the room, a leather-bound tome almost as large as his chest, and brought it up, over, and down, into a vending machine. The machine crumpled under the impact; a siren honked, and it spat out a pile of goodies.

“Do you ever get that feeling,” he asked, “like, how did my life get to this point?”

“Actually, I mostly just go with the flow. A good tourist always leads an interesting life.”

He brought an armful of food over. “How are you doing?”

“Whoever designed this place is an idiot,” she said. She swigged a bottle of blue liquid, then set it down and began panning around the map. “If you hadn’t already figured that one out. Rather than put all the vaults in a row, numbers one, two and four are all in a corridor not too far from here, and number three is just a little past that, adjoining what I might be mistranslating as the Folding Room, but number five is in the opposite direction from here. If the lonely historian is trying to hide, number five would be the logical place to look, but if she isn’t, it’d be smarter to check the four first.”

“If she’s hiding, she can lock herself inside, and we’ll have a dog of a time getting to her either way. Let’s fetch my sister and go for the four.”

“I agree,” she nodded. “Let me see. This says there’s a printer available, but it’s eight rooms away and on the other side of what I’m pretty sure was the bottomless pit room, so I think I’d better just sketch this.” She searched the floor for a pen, went through several that were empty before settling on a red one, and transcribed part of the map to the inside cover of a thin paperback. “Shall we eat as we go?”

The burgers turned out to actually be some sort of oat-like cakes that tasted of honey and nuts. Roger assumed they had to be healthy, and Jill didn’t have the heart to translate the wrappers, which mentioned that they had 18 percent saturated fat. He insisted on finding a rubbish bin for the wrapping before they left.

“Stop laughing at me,” he said. “I know there’s nobody to care, but I always feel guilty if I leave litter lying around.”

“I normally do the same thing,” she admitted. They found a bin half-buried under the sea of books, left the room, crossed the antechamber with the cat, and then skidded to a stop. There was a group of people waiting for them, pointing guns at them.

There were eight of them. Six wore black full-body ballistic armour and carried military-grade assault rifles and other weaponry, split into two fire teams of three. The other two were a man and a woman standing side by side. The man wore a yellow-grey tunic and had a beret on his head and a revolver on his hip, which would have made him look like a colonel, but he was young, toned, and muscular, which made him look like a high school track star. The woman was the only one who didn’t look military: she wore a flattering red-and-black velvet dress cut low and tight to show off her curves, aesthetic rather than functional. Between that and her long blonde-brown hair tied in elaborate braids, she looked like she’d dressed up for a formal party rather than an expedition.

“Hi,” she said.

“Hey, how’s it going,” Roger replied, nervously eyeing the two gun muzzles pointed at him (two were trained on Jill, while the last two tracked around the room).

“Pretty good, pretty good,” she said with a catlike smile, clearly enjoying his discomfort. “And yourself?”

“Oh, cruising. No complaints here.”

“That’s fantastic. By the way, I’m Michelle. This is Aaron,” she said of the man next to her.

“Roger.”

“Jill.”

“Pleased to meet you. Say, could you help a girl out? My crew and I are little lost, and we couldn’t help but overhear you saying something about a map earlier. You couldn’t point us in the right direction, could you?”

“Uh, we can try,” said Roger. Couldn’t help but overhear? If we didn’t hear you, and there are eight of you tromping around in boots and carrying kit … “We can’t find the way out either, but if you want to go somewhere else, maybe …”

Michelle’s smile became fixed. “We’re not looking for a somewhere, we’re looking for a something.”

“… Could you be a little more specific?” he asked.

“Jack?” said Michelle. “A warning shot, please.”

She and Aaron clapped their hands over their ears. Roger and Jill followed suit, but they were a moment too slow; one of the soldiers fired his rifle with a deafening crack, the bullet punching a fist-sized hole into the wall over their heads. Plaster dust drifted out and settled over the book bog. They jumped.

“Do you have any idea how long we’ve been wandering in this stupid library?” Michelle said. “I really don’t have a lot of patience left.”

“Yeah, good for you,” Roger growled, his ears ringing, “but could you pretend for a moment that we weren’t there when you heard about whatever it is that you’re after?”

She gave him an incredulous look. “If you don’t know about it, what are you even doing here?”

“I got lost, and she’s weird.”

Michelle looked at Jill for confirmation.

“I’m not weird,” she said blandly. “We are lost, though, or we were. If you’re looking for some sort of treasure, it’s not that sort of map – we didn’t get it from a retired pirate, you know – but if you feel like telling us what it is, I might be able to make an educated guess. Unless you’re afraid that we’ll steal it out from under your and your private army’s noses?”

Michelle scowled, but she had a point. “I’m looking for a book.”

Roger looked around. If he had to guess, he’d say this one room held maybe a thousand books.

“Well, boy, have I got good news for you,” Jill said.

“The book that holds the secret of immortality,” Michelle clarified.

Roger exchanged glances with Jill. This sounded too good to be true, and Michelle would quite likely shoot them as soon as she either found it or got fed up with searching. On the other hand, refusing to help her wasn’t really an option. The real problem was his sister. He didn’t like leaving her alone with a stalker and heaven only knew what else on the loose, but he couldn’t very well mention her and let Michelle take her hostage. Hopefully she’d have the sense to stay put and keep her head down, and he’d manage to escape and double back to her later.

“We heard a rumour that there’s someone who’s been here awhile and knows what’s what,” he said aloud. “She might be able to give us a clue about where it is, or maybe she has it already. She’s set up in a vault, and a vault seems like the sort of place to hide treasure.”

Aaron looked to Michelle, who worried her lip, thinking it through. Eventually she nodded. “That’s good enough, for a start. May I see the map, please?”

Jill, who still had the paperback in hand, tossed it to her. Michelle caught it and rifled through it, missing the map penned into the inside cover. Her frown deepened.

“The trick isn’t finding a map so much as reading it,” Jill said. “It seems I’m the only one who can. May I have that back?”

Michelle hesitated but threw it back. “I hope you’re not planning on doing anything stupid.”

“Oh, stop blustering. You’re not going to shoot me.”

“Not fatally, no,” Michelle said.

Jill rolled her eyes, exasperated rather than intimidated. “Maybe we can find you something by Dale Carnegie, too. Come on.”