Shad halts in midstride, then makes a course correction back to his table, where he scans some more papers. His assistant jumps up from his chair and tries to help Shad find what he’s looking for, but Shad brushes him aside. Right now he’s remembering that, while he induced Melba Price to testify about Dad routinely keeping adrenaline in his black bag, he never asked her to list the full contents of that bag. God help me, I almost feel sorry for him. As a prosecutor I had some moments like that—rare, thank God, but it only takes one to scar you for life.

“How would you have explained an overdose of fentanyl,” Shad asks, “which would have been detected on autopsy?”

Dad purses his lips like a physics teacher asked to consider some improbable problem. “I would have said Viola was having breakthrough pain. In general, morphine would raise fewer questions postmortem, if for any reason an autopsy was done. Viola knew that. That’s why she chose morphine. But she did tell me that if the morphine proved ineffectual, I should use the fentanyl to be sure.”

Shad’s posture has gone rigid. “You can’t prove a bit of that.”

“I can prove I had the fentanyl in my bag.”

The DA blinks in surprise. “How?”

My ears are roaring. Once again, Shadrach Johnson has stepped off the edge of the map of known answers. It’s the prosecutor’s equivalent of Beyond This Point Lie Dragons.

“When Viola and I first discussed her desire to die peacefully, I prescribed fentanyl, so that we could have it on hand if she actually chose to go through with her plan.”

As Shad shuffles through his papers, his assistant pulls a single sheet from a different pile and hands it to him.

“Doctor, I reviewed the records of Leo Watts, Mrs. Turner’s pharmacist. He had no record of Viola Turner being prescribed fentanyl.”

“I didn’t prescribe it through Mr. Watts’s pharmacy,” Dad says equably. “Leo’s a friend, and a churchgoer, and since I knew how the drug might be used, I didn’t want him troubled by that kind of issue.”

“Or by the police?” Shad says sharply.

Dad inclines his head. “That too, I suppose.”

“Where did you get this fentanyl, Dr. Cage?”

“From a compounding pharmacy. But that isn’t the point, is it? The point is that I had the drug, and I had it with me that night.”

“How can we possibly know that?”

Dad shrugs. “Recall Melba Price, my nurse. She was well aware of the contents of my bag, since she checked its inventory regularly and maintained my drug stocks.”

Shad looks like a man who has awakened from a deep sleep with no idea where he is.