The driver was Alex Morse.

She looked as though she hadn't slept for days. Her voice was shockingly hoarse, her eyes ringed with black, and for the first time since he'd met her, she appeared to be out of control.

"Why haven't you been answering my calls?" she shouted.

"I don't know."

"You don't know?"

"Because I already know what you're going to say."

"You don't know what I'm going to say, goddamn it! Something terrible has happened! Something I couldn't have predicted in a million years."

Chris pedaled up to her open door. "What?"

"One of the husbands that murdered his wife tried to commit suicide last night."

This took Chris aback. "Tried how?"

"Insulin overdose."

"He's still alive?"

Morse nodded.

"In a coma, right?"

"How did you know?"

"I saw that a lot during my residency. People try insulin because it offers hope of a painless death. More times than not they wind up in a permanent vegetative state. Was he diabetic?"

"Yes. Two injections per day."

Chris looked toward the river. "Could have been an accidental overdose."

"I don't think so. But then I don't think it was suicide either."

He said nothing.

Morse took a couple of steps toward him, her eyes boring into his. "What's wrong with you?"

"Nothing," Chris replied.

"Why aren't you at work?"

"Didn't feel like working. Why don't you think it was suicide?"

She studied him as though unsure whether to drop the issue of his mental state. "The guy's name is William Braid. He's from Vicksburg. His wife suffered terribly before she died. If I'm right, and Braid paid for her murder, then we have two possibilities. One, Braid was so consumed by guilt that he couldn't stand to live with himself one more day. Some local gossip supports that scenario. But a couple of his close friends say Braid's ego was so big that he could never kill himself."

"Go on."

"It could also be that whoever Braid hired to murder his wife-Andrew Rusk, for example-decided that an unstable, guilt-ridden client was an intolerable liability. Especially now, with me poking around." Morse looked up and down Cemetery Road. "How hard would it be to put Braid into a permanent insulin coma?"

"Child's play compared to giving someone cancer. Think of the Klaus von Bülow case. Same thing."

Morse's eyes flashed. "You're right. Only in this case, there's no family to get pissed off. So by putting Braid into a coma rather than killing him, the attacker greatly reduced the amount of police scrutiny on the case."

An ancient pickup rumbled by, spewing blue-black exhaust from its tailpipe.

"You look terrible," Chris said. "Why haven't you slept?"

"I drove to Jackson last night. To see my mother. They had to put her into UMC again last night. Her liver's going. Kidneys, too."

"I'm sorry."

"She's close to the end this time. Tons of edema…she's heavily sedated now."

Chris nodded. He'd seen it many times.

"It's weird," Morse said. "Put me on a plane, and I can sleep from wheels-up to the arrival gate. But hospitals…I can't do it."

She seem to expect him to make conversation, but Chris didn't know what to say.

"I did sleep in my car for a couple of hours," she added.

"Sounds risky."

"Not really. I was in the parking lot of your office. I was still asleep when you left."

He felt a prick of guilt.

"I figured you might come out here," she went on. "I've followed Thora when she ran out here."

"Look, Agent Morse-"

"Would you call me Alex, for God's sake?" Exasperation colored her face, darkening the scars around her right eye.

"Okay. Alex. I've heard everything you've told me, okay? I've seen what you've shown me. I know what you want me to do. I've even thought a bit about the feasibility of inducing cancer in human beings. But I didn't feel like listening to any more about it today. That's why I didn't answer your calls."

Her expression had changed from exasperation to something like empathy. "What do you feel like doing?"

"Riding."

She turned up her palms. "Fine. Why not?" She nodded at an approaching car. "But we should get off this road. Where were you going from here?"

He didn't want to mention the Devil's Punchbowl. "I was going to do some sprints in the cemetery, then sit on Jewish Hill for a while."

"What's Jewish Hill?"

Chris pointed to a thirty-foot hill topped with marble monuments and a tall flagpole. The American flag was shamefully weathered, even tattered at the ends of the stripes. "Best place to watch the river go by."

"I can't ride with you today," Alex said, nodding at the empty bike rack attached to her rear bumper. "Could we just take a walk in there? I won't even talk if you don't want me to."

Chris looked away. Could she walk beside him without bringing up her obsession? He doubted it. And talking to Alex Morse would certainly drive him deeper into depression. Yet, oddly enough, she was the only person who might remotely understand what was eating at him. "We're liable to run into people who know me in there, believe it or not. A lot of people run in this cemetery."

Alex shrugged. "If we do, tell them I'm a doctor from out of town. You and Tom Cage are thinking of bringing in a new associate."

Chris smiled for the first time in many hours, maybe days. Then he mounted his bike and pedaled slowly toward the nearest cemetery gate, a wrought-iron monster attached to heavy brick pillars. The whole cemetery was filled with beautiful ironwork from another age. Alex drove through the open gate and parked her Corolla on the grass. Chris chained his bike to her rack, then led her down one of the narrow lanes that divided the tall and silent stones.

They walked some distance without speaking, penetrating ever deeper into the cemetery's interior. Like much of old Natchez, the cemetery had a classical Greek feel to it, thanks largely to the Greek Revival architecture favored by Anglophile cotton planters before the Civil War. Confederate dead were buried here, and also many Americans of national reputation, but the graves of the common people had always interested Chris most.

"Look," he said, pointing toward a dark stone covered with moss.

"Who's buried there?"

"A little girl who was afraid of the dark. She was so afraid that death would be dark that her mother buried her with a glass lid on her coffin. Little steps lead down to the tomb. The mother would go down there every day and read to the dead child from her favorite book."

"My God. When was this?"

"About a century ago."

"Can I see her?"

"Not anymore. They finally had to block it up, because of vandals. Assholes come out here all the time and destroy things. I wish I had the time to sit out here for a few nights in a row. I'd kick the shit out of anybody who tried to desecrate this place."

Alex smiled. "I believe you."

She took the lead and started up a lane that sloped toward the high ground over the river. "You said you've given some thought to my cancer theory."

"I thought you weren't going to talk about that."

"You opened the conversation."

Chris heard himself chuckle. "I guess I did." He walked on for several yards, then said, "I've been doing a little reading in my oncology texts between patients."

"What have you learned?"

"I was right about the complexity of the blood cancers. We don't know what causes ninety percent of them. We do know that most of them have different causes. They can tell that from the changes in various blood cells, and by other factors like tumor-suppressor genes, cellular growth factors, et cetera. This is bleeding-edge medicine we're talking about."

"Was I right about radiation?"

"As far as you went, yes. You could definitely cause a whole spectrum of cancers with radiation. But"-Chris held up a forefinger-"not undetectably. You fire gamma rays into somebody without a qualified radiation oncologist directing the beam, you're going to have severe burns, skin rotting off, vomiting around the clock. Even with qualified personnel, you get serious side effects from radiation therapy. And I'm talking about minimum doses given to cure people."