Presentation? Staging? The ritual itself? A killer with a compulsion to skin. Maybe as a kid, he’d started with small animals or family pets, then, when the fantasy had refused to abate . . .

The ME would check for hesitation marks, if determining jagged edges was even possible given the mounds of thin, curling skin, as well as test for evidence of sexual assault.

But once again, D.D. suffered a nagging sense of discomfort. Those elements were the things a criminal investigator could see. And deep inside, D.D. already suspected that was the wrong track. Indulging, in fact, in exactly what the killer wanted them to focus on.

Why stage things just so, if not to manipulate your audience into seeing exactly what you wanted them to see?

Then it came to her. The thought she’d had in the back of her head. The first and foremost question worth pursuing and the reason she now stood in the dark, her vision deliberately obscured: Why set a scene?

A sound. In the distance. The town house’s front door, easing carefully open? A creak of the stair riser as a heavy foot found the first step? The groan of a floorboard just down the hall?

A sound. Once distant, now closer, and that quickly, Sergeant Detective D. D. Warren realized something she should’ve figured out fifteen minutes ago. Jack’s favorite lullaby, the children’s song she’d been humming under her breath . . . That tune wasn’t coming from solely inside her head.

Someone else was singing it, too. Softly. Outside the bedroom. From elsewhere in the dead woman’s apartment.

Rockabye, baby, on the treetop . . .

D.D.’s hand shot to her sidearm, unsnapping the shoulder holster, drawing her Sig Sauer. She whirled, dropping into a crouch as her gaze scanned the corners for signs of an intruder. No shifts in the blackness, no shadows settling into the shape of a human form.

But then she heard it. A creaking floorboard elsewhere in the apartment.

When the wind blows, the cradle will rock . . .

Quickly, she crept from the bedroom into the darkened hall, leading with her weapon. The narrow corridor didn’t offer any overhead lights. Just more shadows from the glow of neighbors’ apartments casting through the uncovered windows. A wash of lighter and darker shades of gray dancing across the hardwood floor.

But she knew this house, D.D. reminded herself. She’d already trod this hall, judiciously avoiding the pools of vomit, while noticing every pertinent detail.

She reached the top of the stairs, still looking from side to side, then peering down into the inky pool that marked the landing below. The humming had disappeared. Worse than the singing was the total silence.

Then, from out of the darkness, low and lilting: “Rockabye, baby, on the treetop . . .”