“Okay, you’re right,” said Riker, rubbing his eyes, wondering what else he had missed for lack of sleep. And now he had a headache-and a heartache. He reached into the liquor store sack, his idea of a first-aid kit, and pulled out a cold beer to kill the pain.

Following Paul Magritte, Mallory walked between hot coals in cook-stoves and bright flames of burning wood. She heard the humming, the same four notes, over and over, and turned to see the two children huddled on the blanket before an open campfire. Mallory hunkered down beside them, her eyes on the little girl when she asked, “What’s that song?”

The boy moved closer to his sister, and the hum was muffled as he enfolded her in his thin arms and held her close to his breast. Mallory turned her focus to him-interview subject number two. “What’s the name of that song?”

“My kids don’t t alk to strangers,” said a voice from behind her.

The detective rose to a stand and turned around to see the father. He was staring at his son and not liking that wary look in the child’s eyes.

Paul Magritte made the formal introduction to Joe Finn and his children, Peter and Dodie.

Mallory looked down at the girl as she spoke to the father. “Those four notes that Dodie hums-you know the song?”

“No, lady, I got a tin ear. I only know she hums when she’s uneasy.” And it was clear that he laid the blame for this on Mallory.

His face bore fight scars from cuts to the eyes and jaw, but, by stance alone-legs apart, fists at his sides-she knew she had made the right call back at the diner. Boxing was Joe Finn’s t rade, and he had taken a lot of punishment to feed his family. What might he do to protect them? Angry now, he moved between Mallory and his children, wordlessly telling her to go.

Mallory lingered a moment longer, for this man must understand that she did not take orders from civilians. Lessons learned from Markowitz, a lifer in Copland: “Better to take a beating, Kathy. Don’t ever embarrass the Job.” And now, in her own time, she moved on.

Charles Butler scanned the road ahead for signs of gas and lodging. “So we can definitely rule out the idea that she was just badly in need of a vacation.”

“Yeah,” said Riker. “This is definitely not about Mallory joyriding into springtime. She’s hunting solo, and she’s coming apart.” He counted up some of the early warnings for Charles-but not the worst of them. “One day, the little punctuality freak was late for work.”

And that had been the beginning of her slow good-bye. There had been a string of days when she had come in late-if she came in at all. And then she had ceased to answer phone calls, e-mails and knocks at the door. The squad’s commander, Lieutenant Coffey, had put it down to burnout. Other detectives in the squad had ceased to call her Mallory the Machine, for this was something human that they could connect with-lost time and down time, lying awake in the night with the shakes and odd thoughts that could not be driven off except by booze or pills or by eating the gun, muzzle to the mouth, top of the head blown off, so quick-all gone. Drowning cops were never pressured; they were watched over, and that had been Riker’s job from the distance of the curb outside her building. By long tradition, burnout cops were clocked in and out so that docked paychecks would not pile on more anxiety.

Sometimes they came back. Sometimes they died.

“Ta k e that exit,” said Riker. The overpass ahead would give him the high ground he wanted. As the Mercedes climbed the ramp, he lit a cigarette and rolled down a window. “You know what drives most people nuts?” And now the detective had to smile. Well, yeah. The man in the driver’s s e at would know that. Psychology was Charles Butler’s stock and trade. But, what a gentleman, he kept his silence.

“It’s all the things that just aren’t fair.” Riker shot a burnt match out the window. “Mallory’s e arly life was one long bad trick on a little kid.” He squinted into the darkness, as if he could see her as a child out there, cadging loose change from whores and eating out of garbage cans. “I think the kid’s on a mission. She’s counting up all the cheats, the stolen things, lost things. That’s what drives people crazy. Imagine the life she could’ve had- if her mother had lived. Funny thing is, I don’t t hink that other life would’ve measured up.”

“How can you say that?” Charles made a hard right turn at the top of the overpass. “If her mother hadn’t d ied, she wouldn’t have ended up homeless and lost.”

“Lost? Never,” said Riker. “The kid was a born survivor. But let’s say you’re right. In another life, she gets all the perks-two real-live parents, a dog and a swing set in the yard. You think she would’ve turned out better? I don’t. Lou and Helen had her tested when they took her in.”

“Louis told me.” Charles pulled up to a gas pump and turned off the engine. “Her gift was mathematics.”

“Yeah, a math whiz.” Riker stepped out of the car in a futile attempt to pay for the gas, but Charles already had his credit card in the slot. “So she was always meant to be a computer witch. No change there. And she’d still be real pretty. If you saw her on the street, you’d stare long and hard. But then you’d move on. Most every guy would, and you know why.”

Charles watched changing figures on the gas pump. He nodded. He knew. How many men could believe they had a shot with her? Hobbled by that matchless face, she would have been just as unapproachable as she was today.

Riker smiled at the frog-eyed, eagle-beaked man who loved Kathy Mallory. “You think she would’ve turned out more human, Charles? The kind of girl who could see her reflection in mirrors? Well, maybe she’d be a vain little snot, and you wouldn’t w aste six minutes having a beer with her.”

Oh, this was heresy in Charles Butler’s u niverse, where Mallory stood at the exact center, and all else revolved around her. “No,” said Mallory’s apologist. “She would’ve had a real childhood instead of all those feral years. It would’ve made all the difference in how-”

“A lot of her talent came from those years on the street,” said Riker. “Your alternate Mallory wouldn’t be able to open pick-proof locks. So she might let you call her Kathy, but she wouldn’t have the makings of an even better cop than her old man-and I mean back when Lou was in his prime.” And now he played to the other man’s s e nses. “Oh, and the way she walks. You can see it all coming at you, the badge and the gun and all that power. If she’d gotten that other life, she’d be ordinary-or worse.” The detective exhaled a cloud of smoke. “Not the kid that Lou and Helen raised, the one who fascinates you-not my Kathy.”

Riker dropped his cigarette butt on the ground and crushed it with his shoe. “I wouldn’t c hange a minute of her history… not one screwed-up brain cell in her head… nothing. You look at her and see all that potential. And me? I only wish I could make her see what a great kid she is.” And maybe she was a sociopath with the eyes of a stone killer, but Riker had never expected perfection from those near and dear.

Dr. Paul Magritte led Mallory to a Lincoln Town Car. He held the back door open so that she could enter first, but this was not to be. Of course not, and he smiled at his error; she would hardly trust a stranger at her back. Tr ust was not in her stars, her style or her pathology.

He entered first. When she closed the door for privacy, he braced himself.

“Your missing camper,” she said. “Gerald Linden? He’s dead. His body was found at the beginning of the road.”

The doctor closed his eyes. “It can’t be connected. The FBI has been finding bodies along Route 66 for more than a year now, but they’re all children.”

“And you know this how ?”

“The Internet. I ran several online therapy groups for parents of missing children.”