We reached the end of the pool and the point where the sidewalk made a T. We stopped walking because Derek was headed back to the house, but I was going to my car.

“Mitchell Ralston,” he repeated. “If I’m not mistaken, that was the name of one of my father’s night nurses.”

“He had night nurses?”

“This was a while back. Dad was trying a different kind of dialysis where the cycler runs all night while you’re sleeping, instead of during the day. Sidra didn’t want him doing it unobserved; she thought it was too dangerous. So we tried hiring some night nurses, mostly for observation. But in the end, my father found he couldn’t sleep well enough all hooked up to the machine anyway, so he went back to daytime dialysis.”

“What happened to the nurses?”

“We let them go. But Ralston was fired before that anyway. He was bad news, almost from the day he started.”

“Bad news, how?”

Derek pressed a finger against his chin absently as he thought.

“From what I recall, we made the mistake of hiring him without checking his references first. He had sticky fingers. Stole some cash from Dad’s dresser, some jewelry from Mom. We let him go fairly quickly.”

“How long ago was that?”

Derek shrugged.

“I don’t know. Maybe six months ago. Why do you ask?”

I shook my head.

“Too complicated to explain,” I said. “Why didn’t you check his references before hiring him?”

“He came here on a recommendation. From Alan. Ralston had worked for Alan’s aunt or something.”

“What did Alan say when he found out the man was a thief?”

“He was mortified and furious, of course,” Derek replied. “But what can you do? Sometimes things like that happen.”

“I guess so.”

I asked Derek to describe the man.

“Big muscles. Brown hair. Not too bad-looking. Funny haircut, though. Kind of spiked up in the front.”

I thanked Derek for his help, then headed on to my car. As I drove, I thought about what I had just learned. A former nurse! By limiting my search to people whom Wendell would freely allow to inject him with insulin, I hadn’t even considered former employees. Still, if this man had been let go under difficult circumstances, what would Wendell’s reaction have been to the man now appearing in his office, slipping in through the back way? Somehow, I doubted that Wendell would’ve allowed this guy to inject him—unless, perhaps, it was done at gunpoint.

I pulled onto the Schuylkill expressway, knowing I needed to give this information to Duane Perskie because he was running the man’s prints for me. I called him after putting on my earpiece, expecting to leave a message on his voice mail. Much to my surprise, however, he answered on the second ring. I continued to drive as we talked.