“Ask Benton,” I reply. “But I’m betting it has to do with fantasies and power, and maybe the delusional thinking of a damaged brain mixed in. Does Theo Portison by chance have a drone?”

“He’s got shit all over the place including what look like robot parts. The inside of his house looks like Sanford and Son. Think crazy-ass inventor meets homeless person, and it looks like his kitchen is also a lab, and part of it was under a plastic tent like he was making crystal meth or something.”

“Does he have a cough?” I ask, and we’re following my curved corridor to the elevator.

“He says he’s got chronic lung disease, and I can’t remember whose fault he said it was. He’s one of those people who pretty much blames everyone for everything.”

“I’m not surprised he has lung disease.”

“Why?” Marino looks at me. “Just because of a cough?”

“If he works with nanotubes and doesn’t do it in an appropriate clean room or under a HEPA-rated local capture hood—in other words a protected environment—he could have a serious respiratory problem from inhaling fibers and particles too small to see. And as you may remember, the phony Interpol investigator who called you had a cough. That’s what you said. And maybe not so coincidentally, so did the phony Interpol investigator who called Benton.”

“Nanotubes?”

I tell Marino about that next, and we’re in the elevator now, the building restored to its usual sanctity and rhythm. People are coming in to work, and the FBI is no longer here. I’m sure Theodore Portison will keep them busy for a while, and Mahant may decide never to watch an autopsy again.

“I never did have any pizza,” Marino says as the elevator slowly descends.

“That was a long time ago and you weren’t here. How did you know about it?” I ask.

“Oh, I know your little tricks,” he says. “I heard about the ventilation system and that you grossed out Mahant so bad he hit the deck.”

“Almost hit it.” I wave at Georgia as Marino and I pass through the receiving area, headed to the parking lot.

CHAPTER 44

THE LIMITATIONS OF HUMAN flesh, and I should know better than to think I can ignore them.

Driving home is an effort, and I find myself struggling to stay awake as I ease to a halt at a stop sign near the Harvard Divinity School in our Cambridge neighborhood. My blood sugar is low, and I’m feeling the crushing letdown that’s a given after I’ve been fueled by nothing but high-octane adrenaline for hours.