I slip off my pants and draw the bedcovers up to my chest. I want to call Sean and tell him I’m all right, but the truth is, I’m not. In fact, I might be losing my mind. But there’s nothing he can do about that.

As the cell phone drops from my hand, I see an image of Arthur LeGendre lying dead in his gleaming kitchen, black socks pulled up on his white, sticklike legs. Above his corpse floats the killer’s message, painted in blood: My work is never done. Again I see the bite marks on LeGendre’s bloodless flesh, one more set in the endless train of scars and mutilation I’ve witnessed over the past seven years. Is this really my job? How can someone’s life’s work be the analysis of something so brutal, so small, so irritatingly specialized? There has to be more to my choice of career. But what? My father’s mysterious death? Too obvious. “My work is never done,” I murmur, feeling the Valium course through my veins. Earlier today, the sedative I’d swallowed to combat my alcohol withdrawal gave me an unexpected gift: dreamless sleep. I haven’t known such relief for years.

“Thank you,” I whisper to the drug, as though to the god of sleep. My left hand slides over my hip and comes to rest on my lower tummy. My right hand slips out of the covers, reaching for a hand that isn’t there.

“Daddy?” I whisper. “Is that you?”

He doesn’t answer.

He never does, but tonight the aching loneliness that accompanies thoughts of my father isn’t so severe. Valium pads the edges of the pain, easing my descent into sleep. For years I’ve suffered from nightmares, and lately the alcohol I use to deaden them seems to have made them worse. But the Valium is an unfamiliar drug, as fresh and potent as the first drink I ever swallowed.

Tonight sleep enfolds me like the ocean depths on a free dive, a bright upper layer that deepens in color and density as I descend, swimming down, down, down, away from the chaos of the surface, into the blue cathedral of the deep. My sanctuary from the world and from myself. No thoughts here beyond the exigencies of survival. Only peace, the bliss of entering a place where but a handful of humans can go without bottled air, where death is a constant companion, where life is sweeter for the awareness of its fragility.

Here I am weightless.

Shapeless.

An astronaut drifting through deep space without a tether, unconcerned that her life support systems have shut down, that her body must sustain itself or die. Anyone with a lick of sense would kick madly for the surface.

Not me.

Because here I am free.

I don’t know how long I float this way, because time means nothing here. What I do know is that I must be sleeping, because on a real free dive, time means everything. Time is the remaining oxygen dissolved in your bloodstream, the only currency that can buy you depth, and depth is the holy grail, the point of the whole mad exercise. Or it’s supposed to be, anyway. That part confuses me, actually. Because you can never reach the bottom. Not in the real ocean. It’s only back on land that you can do that.

Surfacing now. I know because the sea has slowly stopped trying to drive my wet suit into every opening in my body, and blue-white lightning is flashing above me. A sudden storm? I tense against the inevitable clap of thunder, but it doesn’t come. When the lightning flashes again, a strange sound registers in my mind. Not thunder-not even the lap of waves against the dive boat. It’s the snick of a camera shutter. When I finally break through the surface, I smell acetone, not the ozone that follows a lightning strike. Blinking in confusion, I call out, “Sean? Sean, is that you?”

A dark brown forehead and saucer eyes rise above the footboard of my bed. A nose and mouth follow, the mouth agape in wonder. I’m looking into the face of a black girl of about eight. She has the frozen look of a child who has entered a familiar yard only to find a strange dog waiting for her.

“Who are you?” I ask, half wondering if the girl is real.

“Natriece,” she says, her voice almost defiant. “Natriece Washington.”

I glance around the room, but all that registers is the sunlight pouring through a crack in some curtains. “What are you doing here?”

The girl’s eyes are still wide. “I be here with my auntie. I didn’t mean to make no mess.”

“Your auntie?” The smell of acetone is stronger now.

“Miss Pearlie.”

Suddenly it all comes rushing back. The phone call from Sean. The corpse in the house on Prytania Street. The zoned-out night drive to Natchez. What an irony to find that you do crazier things sober than you ever did drunk.

“What time is it?”

The child gives an exaggerated shrug. “I don’t know. Morning time.”

Pushing down the covers, I crawl to the foot of the bed. The contents of my forensic dental case are spread across the floor in disarray. Natriece is holding my camera; its flash must have caused the “lightning” that awakened me. Among the instruments and chemicals on the floor lies a spray bottle of luminol, a toxic chemical used to detect latent bloodstains.

“Did you spray any of that, Natriece?”

She solemnly shakes her head.

I gently take the camera from her grasp. “It’s all right if you did. I just need to know.”

“I might’ve sprayed a little bit.”

I get out of bed and pull on my pants. “It’s okay, but you need to leave the room while I clean it up. That’s a dangerous chemical in that bottle.”

“I’ll help you clean up. I knows how to clean.”

“Tell you what. Let’s go visit your auntie, and then I’ll come back and deal with this. I haven’t seen Pearlie in a long time.”

Natriece nods. “She told me nobody was out here. She just unlocked the door to get Mrs. Ferry’s wash.”

I take the little girl’s hand and lead her to the door, then flip off the light and walk into the hall. Natriece lingers behind, standing with her back to me, looking into the dark room. “Did you leave something?” I ask.

“No, ma’am. I just looking at that.”

“What?”

“That there. Did I do that?”

I look over the girl’s head. On the floor near the foot of my bed, a greenish blue glow hovers in the darkness. The luminol has reacted with something on the carpet. The chemical registers false positives with several compounds, one of them household bleach.

“It’s all right,” I tell her, dreading my mother’s reaction to the mess Natriece has made.

“Freaky,” she says. “That looks like Ghostbusters or something.”

Stepping around Natriece, I look down at the luminescence on the floor. It’s not diffuse, as I had thought, but well defined. Suddenly, an eerie numbness spreads through my body.

I’m looking at a footprint.

I felt the same numbness twenty-three years ago, when my grandfather turned away from the first corpse I ever saw, knelt before me, and said, “Baby, your daddy’s dead.”

“Natriece, stay back.”

“Yessum.”

Actually, it isn’t a footprint at all, but a boot print. I only register this fact because now another ghostlike image has taken shape beside it. The image of a bare foot, much smaller than the boot.

A child’s foot.

With slow insistence, a percussive hiss intrudes into my concentration. Subtly at first, but growing steadily to a soft roar. It’s the sound of rain drumming on a tin roof. Which makes no sense, because the slave quarters has a shingle roof-not tin-and I’m standing on the first of two floors. But I’ve heard this sound before, and I know it for what it is. An auditory hallucination. I heard the same metallic patter a week ago, at the Nolan murder scene. Just before my panic attack. I was staring down at the retired CPA’s naked corpse and-

A rapid beat of footsteps startles me from my reverie. Natriece has bolted down the hall. A scream cuts the air in the bedroom.

“Nanna! Nanna! Nanna!”