The School of Night by Louis Bayard

on the other side of the Anacostia. He stared down that vault as if it were a meth lab.
    â€œIt’s got vents,” he said. “Blowers.”
    â€œTrue,” I said.
    â€œIn working order?”
    â€œAs far as I know.”
    He gave his tie a delicate twist. “Then there’s no reason for that woman to suffocate. She should be alive right now.”
    â€œDetective?” said Clarissa, taking a step forward. “If I may?”
    A crease lined August Acree’s brow as he squared himself toward her.
    â€œYour name, ma’am?”
    â€œClarissa Dale. I think I could be of help here.”
    â€œAh.”
    You can say ah in many different ways, but you can’t make it sound much less encouraging than that.
    â€œBest I can tell,” she said, “Mr. Wax’s vault is built along the same lines as a bank vault. Which means it needs some way of suppressing fires. Your classic sprinkler system, that’s not going to work because it’s going to soak the books. Might as well just let them burn, right?”
    The crease in the detective’s forehead got deeper.
    â€œNow most banks,” Clarissa said, “use a gas called halon. Pretty safe, not too toxic. But if you’re not a regulated entity, you can get away with using carbon dioxide.”
    â€œCarbon dioxide.”
    â€œNow don’t worry, Detective, I won’t touch a thing. I’ll just direct your attention to the vault’s roof. Assume for a second that a fire’s broken out. In that event, what happens is the carbon dioxide gets released from the ceiling, see? It floods the vault, it squeezes out the oxygen so the fire won’t have anything to react with. Imagine a hand , okay? Pressing all the oxygen to the floor.”
    â€œSo…” Acree took a step toward the vault. “If someone’s actually inside when this is happening…”
    â€œThey’d have a few minutes is all. And if they know how the system works, they’re gonna keep low , because that’s where all the oxygen is. If there’s any left. Now when we found Miss Pentzler, she was all the way down to the ground.” Clarissa knelt in an attitude of prayer. “Her face was pressed against the door crack. My guess? She was fighting for air.”
    The detective gave his tie another twist.
    â€œSo how’d the smoke alarm get triggered?”
    The question was answered by one of his own techs, emerging from the vault with a plastic bag raised like a war trophy. Inside was a soggy cigarette butt, no more than an inch long. Far too small, you’d have thought, to merit all the scrutiny it now received.
    â€œWas Miss Pentzler a smoker?” asked Detective Acree.
    â€œNot that I ever saw,” I said. “She might have been.”
    â€œGeez, you’re not a smoker, but you bring a lit cigarette into a vault, then get yourself locked inside. I don’t know. In my world, that’s…” He made a whistling sound.
    â€œMaybe it was someone else’s cigarette,” I said.
    â€œThen where’s the someone else? If that cigarette was still burning, whoever it was couldn’t have been far off. And forget the cigarette for a second. If Miss Pentzler knew what a fix she was in, why didn’t she call someone? Building management, nine-one-one?”
    With some regret, I drew Lily’s BlackBerry from my pocket.
    â€œWe found it by the sofa,” I said, fighting to keep my voice level.
    Detective Acree watched as the phone was sealed in a bag. Then he turned his eyes back to the vault.
    â€œNo air,” he said, half to himself. “No phone. No one to hear her scream.”
    â€œNo books ,” added Clarissa.
    Acree arched his eyebrows. “Sorry?”
    â€œDetective, I don’t mean to minimize Miss Pentzler’s death, but there’s another pretty serious crime that’s taken place here. Mr. Wax’s whole collection has gone