At the mention of the doctor it was Ms. Chigwell’s turn to tremble a little.

“You’re losing it,” Art said angrily. “How’re you going to get her back into the house without the daughter seeing you? Anyway, she’ll know her mother’s gone—she’s probably roused the neighborhood by now as it is. Better just dispose of Louisa here and set a trap for Warshawski someplace else. It’d be best if they were both gone.”

“I’ll do it for you,” the cold voice said flatly. “I’ll get rid of them both and the daughter, too, if you want. But I can’t if I don’t know why you’re so desperate to see them put away. It wouldn’t be ethical.” He used the last word without any hint of irony.

“Damn you, I’ll take care of things myself,” Art muttered furiously.

“Fine,” the voice said irritatingly. “Either way it’s fine. You tell me what they know and I’ll have that, or you kill them yourself and I’ll have that. It’s a matter of complete indifference to me.”

Jurshak was silent for a minute. “I’d better see how the doc is making out.”

His footsteps echoed and disappeared. He’d gone inside. So Louisa wasn’t in the ambulance. Presumably one of the flat-voiced man’s sidekicks was waiting in its interior instead of Louisa—they’d left it temptingly in the middle of the yard so I’d head straight to it.

How to get past the cold-voiced man standing at the entrance was a tougher question. If I sent Ms. Chigwell out as a diversion, she’d be a dead diversion. I was wondering if we could jimmy a door or a window around the side when the man solved the problem for us. He strolled out to the center of the yard, where he stopped to knock on the back of the ambulance. The rear door opened a crack. He stood talking through the opening.

I tapped Ms. Chigwell on the shoulder. She stood up with me and we sidled slowly to the shadow of the wall. While we watched, the ambulance door shut again and the cold-voiced man wandered on out to the gate. As soon as he was on the far side of the vehicle, I crouched low and sprinted around the corner to the plant entrance. Ms. Chigwell’s footsteps sounded softly behind me. The ambulance shielded us from the view of the gate sentry and we made it inside without hearing any outcry.

We were on a concrete apron outside the plant floor. The sliding steel curtain that separated the manufacturing area from the main entrance was shut, but a normal-sized door next to it stood ajar. We quickly darted through it, shutting it softly behind us, and found ourselves immediately in the plant.

We walked on tiptoe, although the noises around us would have drowned any sounds we made. The pipes let out their intermittent belches of steam and the cauldrons bubbled ominously under the dull green safety lights. Fritz Lang had invented this room. Presently we would come to the end and find only cameramen and laughing actors. A drop of liquid fell on me and I jumped, convinced I’d been poisoned with a toxic dose of Xerxine.