“Okay, then,” I said to Gard. “Why don’t we start with everyone who knew the location of Marcone’s panic room.”

Gard narrowed her eyes, studying me. She looked better. Granted, it’s difficult to look much worse than disemboweled, but even so, she’d been reduced from ten miles of bad road to maybe two or three. She was sitting up in her cot, her back resting against the wall of the workshop, and though she looked pale and incredibly tired, her blue eyes were clear and sharp.

“I don’t think so,” she said quietly.

“There’s not going to be much need to keep Marcone’s secrets once he’s dead, or under the control of one of the Fallen.”

“I can’t,” she said.

“Oh, come on,” I said, throwing up my hands. “Hell’s bells, I’m not asking you for the launch codes to nuclear missiles.”

She took a deep breath and enunciated each word. “I. Can’t.”

From the workbench Hendricks rumbled, “S’okay. Tell him.”

Gard frowned at his broad back but nodded once and turned to me. “Comparatively few people in the organization were directly aware of the panic room, but I’m not sure that’s our biggest concern.”

The change in gears, from stonewall to narration, made me blink a little. Even Michael glanced up, frowning at Gard.

“No?” I asked. “If that’s not our biggest concern, what is?”

“The number of people who could have pieced it together from disparate facts,” Gard replied. “Contractors had to be paid. Materials had to be purchased. Architects had to be hired. Any of a dozen different things could have indicated that Marcone was building something, and piqued someone’s curiosity enough to dig deeper.”

I grunted. “At which point he could probably find out a lot by talking to the architects or builders.”

“Exactly. In this instance he was unusually lax in his standard caution when it came to matters of security. I urged him to take conventional measures, but he refused.”

“Conventional measures,” I said. “You’re talking about killing everyone who worked on it.”

“Secret passages and secret sanctums are quite useless if they aren’t secret,” Gard replied.

“Maybe he didn’t feel like killing a bunch of his employees to cover his own ass.”

Gard shrugged. “I’m not here to make moral judgments, Dresden. I’m an adviser. That was my advice.”

I grunted. “So who would know? The builders. People handling books and paychecks.”

“And anyone they talked to,” Gard said.

“That makes the suspect pool a little larger than is useful,” I said.

“Indeed it does.”

“Stop,” I said. “Occam time.”

Gard gave me a blank stare. Maybe she’d never heard of MC Hammer.

“Occam?” she asked.

“Occam’s razor,” I said. “The simplest explanation is most often correct.”

Her lips quivered. “How charming.”

“If we define a circle of suspects that includes everyone who might possibly have heard anything, we get nowhere. If we limit the pool to the most likely choices, we have something we can work with, and we’re much more likely to find the traitor.”