Predictably, Jacob swells with pride. “I suppose I have time for that.”

“That’s great,” Matson replies, “because we’re stumped. We’ve got some cold cases-and a few active ones-that have us scratching our heads. And after seeing you draw conclusions about the hypothermic guy, I know that you’re incredibly well-versed in forensic criminology.”

“I try to keep up-to-date,” Jacob says. “I subscribe to three journals.”

“Yeah? Impressive.” Matson opens up the door that leads into the bowels of the police station. “Why don’t we go somewhere a little more private?”

Using his love of CSI to entrap Jacob into giving a statement about Jess’s death is like holding out a syringe of heroin to an addict. I am furious at Matson for being so underhanded; I am furious at myself for not realizing that he would have his priorities, just like I had mine.

Flushed with anger, I start to follow them through the doorway but am stopped by the detective. “Actually, Emma,” he says, “you’ll have to wait here.”

“I have to go with him. He won’t understand what you’re asking him.”

“Legally, he’s an adult.” Matson smiles, but it doesn’t reach his eyes.

“Really, Mom,” Jacob adds, his voice brimming with self-importance. “It’s fine.”

The detective looks at me. “Are you his legal guardian?”

“I’m his mother.”

“That’s not the same thing,” Matson says. “I’m sorry.”

For what? I wonder. For seducing Jacob into believing he’s on his side? Or for doing the same to me?

“Then we’re leaving,” I insist.

Matson nods. “Jacob, it’s your decision. Do you want to stay with me, or do you want to go home with your mom?”

“Are you kidding?” Jacob beams. “I want to talk to you, one hundred percent.”

Before the door closes behind them, I have already taken off at a dead run toward the parking lot.

All is fair in love, war, and interrogation. By that I mean that if I can convince a suspect I’m the second coming of his long-dead grandma and the only way to salvation is to confess to me, so be it. None of which accounts for the fact that I cannot get Emma Hunt’s face out of my mind, the minute she realized that I had betrayed her and was not going to allow her to sit in on my little chat with her son.

I can’t bring Jacob into the interrogation room, because Mark Maguire is still there cooling his heels. I’ve left him with a sergeant who’s currently doing a six-month stint with me to figure out whether or not he wants to take the test to make detective. I can’t unarrest Mark until I know for sure I’ve got the right suspect in my sights.

So instead, I lead Jacob to my office. It’s not much bigger than a closet, but it has boxes of case files all over the place and a few crime scene photos tacked up on the corkboard behind my head-all of which should get his adrenaline flowing. “You want a Coke or something?” I ask, motioning to the only other spare seat in the room.

“I’m not thirsty,” Jacob says. “I wouldn’t mind something to eat, though.”

I rummage through my desk drawers for emergency candy-if I’ve learned anything on the job it’s that when everything seems to be going to hell in a handbasket, a pack of Twizzlers can help you gain some perspective. I toss him some from my stash of last year’s leftover Halloween candy, and he frowns.

“They’re not gluten-free,” Jacob says.

“Is that a bad thing?”

“Do you have any Skittles?”

I cannot believe we’re negotiating candy, but I rummage through the bowl and come up with a packet of Skittles.

“Sweet!” Jacob says. He tears a corner and tips the edge right into his mouth.

I lean back in my chair. “You mind if I tape this? That way, I can have it typed up just in case we come up with any terrific insights.”

“Oh, sure. If that’s helpful.”

“It will be,” I say, and I hit the button on the tape recorder. “So how’d you know that guy died of hypothermia, anyway?”

“Easy. There weren’t any defense wounds to his arms; there was blood but no overt trauma… and of course the fact that he was in his underwear was a dead giveaway.”

I shake my head. “You made me look like a genius in front of the medical examiner,” I say.

“What’s the most bizarre case you’ve ever heard about?”

I think for a moment. “A young guy jumps off the top of a building, intending to commit suicide, but sails past an open window at the exact moment a gunshot is fired through it.”

Jacob grins. “That’s an urban legend. It was debunked by the Washington Post in 1996 as part of a speech given by a former president of the American Academy of Forensic Sciences, to show the legal complications of forensic analysis. But it’s a good one, all the same.”

“How about you?”

“The Texas Eyeball Killer. Charles Albright-who taught science-killed prostitutes and surgically removed their eyeballs as trophies.”

He grimaces. “Obviously that’s the reason I never really liked my bio teacher.”

“There are a lot of people in this world you’d never suspect as murderers,” I say, watching Jacob carefully. “Don’t you think?”

For just the tiniest flicker of a moment, a shadow crosses over his face. “You’d know better than me,” he says.

“Jacob, I’m sort of in a predicament. I’d like to pick your brain about a current case.”

“Jess’s,” he states.

“Yes. But that’s tricky, because you knew her. So if we’re going to talk openly, you’ll have to waive your rights to not discuss it. You get what I’m saying?”

He nods and begins to recite Miranda. “I have the right to remain silent. Anything I say can and will be used against me in a court of law. I have the right to have an attorney present during questioning. If I cannot afford an attorney, one will be appointed for me…”

“Exactly,” I murmur. “I actually have a copy of that here. If you can initial it here, and sign at the bottom, then I can prove to my chief that you didn’t just memorize it-you understood what it meant.”

Jacob takes a pen from me and quickly scrawls his name across the paper I’ve prepared. “Now can we talk about it?” he asks. “What have you got?”

“Well, the backpack was a disappointment.”

“No prints?”

“Only ones we could match to Jess herself,” I say. “Something else interesting turned up at the house-a screen was cut and the window jimmied open.”

“You think that’s how the perp got inside?”

“No, because the door wasn’t locked. We did, however, find boot prints under the window that matched footwear Jess’s boyfriend owns.”

“There was a great CrimeBusters episode once where the exterior footprints didn’t show up until it snowed-” Jacob breaks off, editing himself. “So Mark kills Jess and then tries to make it look like something else-a break-in-by cutting the screen and knocking over the stools and the mail and the CDs?”

“Something like that.” I glance down at his hands-like Maguire’s, they are injury-free. “What’s your take? How hard would it be to reorganize a crime scene to mislead the investigators?”

Before he can answer, my cell phone rings. I recognize the number; it’s Basil, who’s accompanied the medical examiner back to the hospital. “Could you excuse me for a minute?” I ask Jacob, and I step into the hall and close the door behind me before answering the phone. “What have you got?”

“In addition to the scrapes on her back and contusions on the throat and upper arms, there are some more in the periorbital region-”

“English, Basil.”

“Raccoon eyes,” he says. “She’s got a broken nose and a skull fracture. Cause of death is subdural hematoma.”

I try to imagine Jacob Hunt throwing a right hook to Jess Ogilvy’s face, hard enough to crack her skull. “Great. Thanks.”

“That’s not all,” Basil answers. “Her underwear was on backward, but there’s no evidence of sexual assault. Her face was washed clean-there were traces of blood in the hairline. And that missing tooth? We found it.”