Inside the MRI suite, Benton Wesley watches his patient through a partition of Plexiglas. The lights are low, multiple video screens illuminated along the wraparound counter, his wristwatch on top of his briefcase. He is cold. After several hours inside the cognitive neuro imaging laboratory, even his bones are cold, or at least that’s how it feels.

Tonight’s patient goes by an identification number, but he has a name. Basil Jenrette. He is a mildly anxious and intelligent thirty-three-year-old compulsive murderer.Bentonavoids the term serial killer. It has been so overused, it means nothing helpful and never did except to loosely imply that a perpetrator has murdered three or more people over a certain period of time. The word serial suggests something that occurs in succession. It suggests nothing about a violent offender’s motives or state of mind, and when Basil Jenrette was busy killing, he was compulsive. He couldn’t stop.

The reason he is getting his brain scanned in a 3-Tesla MRI machine that has a magnetic field sixty thousand times more powerful than the earth’s is to see if there is anything about his gray and white matter and how it functions that might hint at why.Bentonhas asked him why numerous times during their clinical interviews.

I would see her and that was it. I had to do it.

Had to do it right that minute?

Not right there on the street. I might follow her until I figured it out, came up with a plan. To be honest, the more I calculated, the better it felt.

And how long would this take? The following, the calculating. Can you approximate? Days, hours, minutes?

Minutes. Maybe hours. Sometimes days. Depends. Stupid bitches. I mean, if it was you and you realized you were being abducted, would you just sit there in the car and not even try to get away?

Is that what they did, Basil? They sat in the car and didn’t try to get away?

Except for the last two. You know about them because that’s why I’m here. They wouldn’t have resisted, but my car broke down. Stupid. If it was you, would you rather be killed right there in the car or wait to see what I’m going to do to you when I get you to my special spot?

Where was your special spot? Always the same place?

All because my damn car broke down.

So far, the structure of Basil Jenrette’s brain is unremarkable except for the incidental finding of a posterior cerebellar abnormality, an approximately six-millimeter cyst that might affect his balance a little, but nothing else. It is the way his brain functions that isn’t quite right. It can’t be right. If it were, he wouldn’t have been a candidate for the PREDATOR research study, and he probably wouldn’t have agreed to it. Everything is a game to Basil, and he is smarter than Einstein, thinks he is the most gifted person on earth. He has never suffered one moment of remorse for what he’s done and is quite candid in saying that he would kill more women given the opportunity. Unfortunately, Basil is likeable.

The two prison guards inside the MRI suite vacillate from confused to curious as they stare through the glass at the seven-foot-long tube, the bore of the magnet, on the other side. The guards wear uniforms but no guns. Weapons aren’t allowed in here. Nothing ferrous, including handcuffs and shackles, is permitted, and only plastic flex-cuffs restrain Basil’s ankles and wrists as he lies on the table inside the magnet, listening to the jarring knocks and wonks of radiofrequency pulses that sound like infernal music played on high-voltage power lines-or that’s what Benton imagines.

“Remember, this next one is color blocks. All I want you to do is name the color,”Dr. Susan Lane, the neuro psychologist, says into the intercom. “No, Mr. Jenrette, please don’t nod your head. Remember, the tape is on your chin to remind you not to move.”

“Ten-four,” Basil’s voice sounds through the intercom.

It ishalf past eightat night andBentonis uneasy. He has been uneasy for months, not so much worried that the Basil Jenrettes of the world are going to suddenly explode into violence inside the gracious old brick walls of McLean Hospital and slaughter everything in sight, but that the research study is doomed to failure, that it is a waste of grant money and a foolish expenditure of precious time.McLeanis an affiliate ofHarvardMedicalSchool, and neither the hospital nor the university is gracious about failure.

“Don’t worry about getting all of them right,” Dr. Lane is saying over the intercom. “We don’t expect you to get all of them right.”

“Green, red, blue, red, blue, green,” Basil’s confident voice fills the room.

A researcher marks down results on a data-entry sheet while the MRI technician checks images on his video screen.

Dr. Lane pushes the talk button again. “Mr. Jenrette? You’re doing an excellent job. Can you see everything okay?”

“Ten-four.”

“Very good. Every time you see that black screen, you are nice and still. No talking, just look at the white dot on the screen.”

“Ten-four.”

She releases the talk button and says toBenton, “What’s with the cop jargon?”

“He was a cop. That’s probably how he was able to get his victims into his car.”

“Dr. Wesley?” the researcher says, turning around in her chair. “It’s for you. Detective Thrush.”

Bentontakes the phone.

“What’s up,” he asks Thrush, a homicide detective with the Massachusetts State Police.

“I hope you weren’t planning on an early bedtime,” Thrush says. “You hear about the body found this morning out byWalden Pond?”

“No. I’ve been locked up in this place all day.”

“White female, unidentified, hard to tell her age. Maybe in her late thirties, early forties, shot in the head, the shotgun shell shoved up her ass.”

“News to me.”

“She’s been autopsied already, but I thought you might want to take a look. This one ain’t the average bear.”

“I’ll be finished up in less than an hour,”Bentonsays.

“Meet me at the morgue.”

The house is quiet and Kay Scarpetta walks from room to room, turning on every light, unsettled. She listens for the sound of a car or a motorcycle, listens for Marino. He is late and hasn’t returned her phone calls.

Unsettled and anxious, she checks to make sure that the burglar alarm is armed and the floodlights are on. She pauses at the video display on the kitchen phone to make sure the cameras monitoring the front, back and sides of her house are operating properly. Her property is shadowy in the video display, and dark images of citrus trees, palms and hibiscus move in the wind. The dock behind her swimming pool and the waterway beyond are a black plain dabbed with blurred lights from lamps along the seawall. She stirs tomato sauce and mushrooms in copper pots on the stove. She checks dough rising and fresh mozzarella soaking in covered bowls by the sink.

It is almost nine, and Marino was supposed to be here two hours ago. Tomorrow she is tied up with cases and teaching, and she doesn’t have time for his rudeness. She feels set up. She has had it with him. She has worked nonstop on the Johnny Swift alleged suicide for the past three hours, and now Marino can’t bother to show up. She is hurt, then angry. It is easier to be angry.

She is very angry as she walks into her living room, still listening for a motorcycle or a car, still listening for him. She picks up a twelve-gauge Remington Marine Magnum from her couch and sits down. The nickel-plated shotgun is heavy in her lap, and she inserts a small key in the lock. She turns the key to the right and pulls the lock free from the trigger guard. She racks the pump back to make sure there are no cartridges in the magazine.