I turned my eyes to the ceiling. And blinked. The stairs terminated here, and the roof was only just out of arm’s reach above me. But . . . eight meters? I walked back to the stairs. “Excuse me?” I called.
“Yes?”
“Is there anything above this level? I mean, another floor?”
“Another . . . ?” I heard Bull’s heavy tread on the steps. Looking at the book I was holding, I rubbed one of the open sheets—a page. It was covered in columns of heavy, immobile black lettering and numbers. The font was execrably wobbly and uneven, and there were numerous wavering strikethroughs and overprints, almost as if someone had tried to create a parody of a spreadsheet by hand. On impulse, I ran a slightly damp finger down a column of figures. They smeared, like a retina in proximity to a strong magnetic field, and when I rubbed my finger in the opposite direction they smeared even more, into near illegibility. More questions: How had she gotten all these books into this apartment, if they were so easily damaged by water? And again: Why?
Bull arrived. “What’s that you’ve got?” he asked.
“A book.” I peered at it, trying to read what I’d found. It looks like . . . yes, there was a lack of cross-references and icons, not to mention keys, but the columns made sense if I squinted at them and assumed they were the raw data content of a double-entry ledger. Minus the macros and active content, of course. “It looks like someone was keeping accounts on, what’s the stuff called, paper.” I glanced up at the ceiling: It appeared to be a seamless expanse, sky blue and glowing with artificial daylight. “Using a pigment, uh, ink, that dissolves in water.” I glanced down at the floor, then over toward the trapdoor beside the stairwell opening. I thought about the living space below it, the moon pool opening onto the vestibule exit, and a tentative hypothesis suggested itself to me. “There’s no way in or out of here that doesn’t go through water, is there?”
“Give that here.” Bull reached for the book, and I passed it to him; there were plenty more on the shelves.
“Be careful not to get it wet,” I said. “Did you or any of the other investigators read these?”
“I’ll have to check the case web before I can answer that.” Bull went walleyed for a moment, communing with his memory palace. “Ah, yes and no. They were noted as an unusual collection of artifacts, and so one of the detectives took a look at them—examined a representative sample, exterior and interior, dusted for codon samples, checked isotope ratios to identify the planet of origin, that sort of thing. There was nothing obviously anomalous about them, and a distributed net search for some random samples of the content didn’t throw anything up, so the case committee concluded that Ana Graulle-90 was merely a collector of such things. A historian of accountancy practices collects archaic ledgers, yes?” He focused on me abruptly. “Do you disagree?”
“Well.” I considered my next words carefully. “First, is there anything above the ceiling?”
“Let me see.” Serjeant Bull’s uniform might be motley, but his belt carried numerous pouches. From one of these he pulled a compact device that he held to his eyes as he studied the underside of the roof. “Odd. It’s opaque.”
“Opaque?” I asked: “What do you mean?”
He held the device toward me, and I saw that it had a compact screen built into a visor, with some sort of sensor on the outside. “Magic police goggles: They’re a terahertz imager. You use it to see through nonconductive surfaces. Water and metals reflect terahertz radiation, so they show up. But the ceiling is opaque.”
“So if Ana or whoever lived here”—he looked at me narrowly—“wanted a secret level that the police would be unable to find . . . ?”
“These condos are recycled fuel tanks, their outer walls are sheet steel.” Serjeant Bull reached up and rapped on the ceiling. “Which”—he paused—“is very interesting, because there should be at least three meters of air above our heads. Hmm.”
“It might be a false ceiling,” I equivocated. “There might not be anything suspicious about it.”
“But you don’t think so.” Serjeant Bull increasingly struck me as one of those thinkers who is neither fast nor shallow: not one to rapidly and incisively solve problems on the fly but not likely to miss anything either, once he had time to give the issue at hand due consideration. “And your reaction downstairs was that you couldn’t imagine your sib living here. Why is that?”
“We—” I gathered my thoughts. “I did not know her particularly well, but we shared a common ancestor and we have corresponded, over the decades. The living space downstairs is tasteless. It’s full of pointless junk. Serjeant, Ana grew up aboard a generation ship and lived by preference in deep-space habs, out in the cold yonder. Which is not to say that she might not have harbored a secret fetish for deadweight and finally felt free to indulge it once she had the opportunity, but that stuff is massive. And mass costs.” I swallowed. “And now this . . . this doesn’t figure. None of it. Not the bed, not the books. It’s just not like something one of us would do! Especially the books, unless . . .”
I reached over to the nearest shelf and took another bound volume. Opened it. More tallies marching down the page, endlessly, totaled at the bottom and carried overleaf in wobbly lettering. Smeary ink. The description field didn’t help much: They were all ten-digit alphanumerics. I would need an inventory table to make sense of it. But the quantities and prices all added up, that much I could see. “These are account ledgers. There must be a, what do you call it, a pen somewhere near here.” I looked over at the table. There was a chair beside it, as one might expect. “She was keeping books for somebody, by hand, using these books rather than a calculator or any other kind of publicly accessible memory. A truly ancient method, but very robust! Why, if she removed her soul chips while she worked, there might be no record whatsoever of what was happening here that could be detected by remote searchers. Unless you hooked her up to a debugger and questioned her”—I shivered—“you’d get nothing.”
Serjeant Bull looked around at the room, clearly seeing it in a new light. “You say the pigment dissolves in water. Hmm. And this paper: waterproof, yes or no?”
“No.” I racked my brains, thinking back to an ancient history class: “It dissolves in water. And the only way in or out of here is through a wet lock. Someone who was sent to grab the books and didn’t know what precautions to take to protect them would ruin them completely in the process, destroying the accounts.” I looked up at the ceiling again. “That trapdoor by the staircase. Did anyone try lowering it— Wait, don’t!”
Bull stopped in midstride. “Why? What do you think would happen?” he asked mildly.
“There’s something wrong with this whole setup,” I began. “The pigment Ana—or whoever—used in these books. Did anyone send a sample for analysis? To find out where it came from?” My head was spinning, correlating disconnected data. Water-soluble ink, used to make marks on fibrous water-absorbent paper. A cylindrical dwelling, the ledgers stored upstairs. Trapdoor below, opaque false ceiling above. Only way in and out via a water lock underneath. “It’s all about the books. If you take them out via the front door, the ink will dissolve. And you can’t get at what’s in them via any kind of search algorithm. This whole room was meant to be a secret, wasn’t it? Hidden in full view and disguised as a dwelling. Someone hired Ana to keep books for them, and whatever they were accounting for, it had to stay invisible and out of sight.” I was thinking furiously. “But suppose . . . suppose they didn’t know about Ana’s other connections? Our correspondence, or the fact that she was expecting me to arrive? Maybe they hired her to do the job without telling her what it was, first.”