“Pierce insisted on keeping everything from her. Even hid his headache medication in a locked box in his darkroom. I tried to convince him to communicate with her more openly, but he was adamant. Their entire relationship was like that, Alex. Each of them talked to me, and I translated. In that sense, she was the perfect woman for him—stubborn, independent, fiercely private. He could be a profoundly unmovable man. Part of what made him a good detective, I suppose.”

“Do you think the night terrors were neurological, or unfinished business come back to haunt him?”

“Maybe both,” he said. “Nothing unusual was found at his autopsy, but that means nothing. I’ve seen postmortem brain tissue that looks like Swiss cheese and turns out the patient was functioning perfectly. Then you come across perfectly healthy cerebral cortexes in people who fall apart neurologically. At the core, we humans defy logic. Isn’t that why we both became doctors of the soul?”

“Is that what we are?”

“We are, son—Alex, I am sorry for concealing things from you. At the time I believed it was the right thing to do. But that girl . . . the killer’s still out there.” Tears filled his eyes. “One sets out to heal and ends up being complicit.”

I placed a hand on his narrow, soft shoulder.

He smiled. “Therapeutic touch?”

“Friendship,” I said.

“The purchase of friendship,” he said. “Cynics coined the term to demean what we do. Sometimes I wonder about the direction my own life has taken . . .”

We strolled toward the gravel pathway.

I said, “What kind of relationship did Schwinn and Burns develop?”

“Once I knew Pierce could be trusted, I brought him out here. They began talking. Relating. Pierce ended up helping Bill. He’d come out from time to time, clean the house, wheel Bill around.”

“And now Pierce is gone, Burns remains as the last living witness to the Ingalls murder.”

Bert stared at the earth and kept walking.

I said, “You call him Bill. What’s his new surname?”

“Is that important?”

“It’s going to come out, eventually, Bert.”

“Is it?” he said, lacing his hands behind his back. He steered me toward the open space at the front of the house. “Yes, I suppose it is. Alex, I know you need to talk to him, but as I told you, he has very little time left, and like most ex-addicts, his self-assessment is brutal.”

“I’ll be mindful of that.”

“I know you will.”

“When we spoke earlier,” I said, “you made a point of mentioning that heroin addicts were unlikely to be violent. You were trying to steer me away from Burns’s trail. Caroline Cossack’s, as well, by pointing out to me that females were unlikely to be involved in that kind of sexual homicide. All true, but how’d they end up witnessing the murder?”