“No bleach, and to be safe, we definitely should try DNA,” she says. “And although epithelial cells are common in GSR, that’s only when a suspect’s hands are dabbed with double-sided sticky carbon tape. So what we’re seeing, if it’s skin, doesn’t make sense unless the skin cells were transferred by the killer’s hands. Or the cells were already on the windowpane. But what would be peculiar about the latter is the glass was cleaned, wiped off, and we’re seeing fibers from that. Consistent with white cotton, and the dirty T-shirt I found in the laundry basket is white cotton, but what does that mean? Not much, really. The laundry room would be a landfill of microscopic fibers.”

“At this magnification, everything becomes a landfill.” Dr. Franz clicks the mouse, and manipulates and repositions, and the electron beam strikes an area of broken glass.

Beneath the polyurethane foam, which dried clear, cracks look like canyons. Blurred white shapes might be more epithelial cells, and lines and pores are a skin imprint from some part of the body hitting the glass. There are fragments of hair.

“Someone ran into it or punched it?” Dr. Franz says. “That’s how it was broken, maybe?”

“Not with a hand or the bottom of a foot,” Scarpetta points out. “No friction ridge detail.” She can’t stop thinking about Rome. She says, “Instead of the GSR having been transferred from someone’s hands, maybe it was in the sand.”

“You mean before he touched it?”

“Maybe. Drew Martin wasn’t shot. We know that for a fact. Yet traces of barium, antimony, lead are in the sand found in her eye sockets.” She goes through it again, trying to sort it out. “He put the sand in there and then glued her eyelids shut. So what appears to be GSR could have been on his hands and was transferred to the sand, because certainly he touched it. But what if the GSR is there because it was already there?”

“First time I’ve ever heard of anybody doing something like that. What kind of world do we live in?”

“I hope it will be the last time we hear of somebody doing something like that, and I’ve been asking the same question most of my life,” she says.

“Nothing to say it wasn’t already there,” Dr. Franz says. “In other words, in this case”—he indicates the images on the screen—“is the sand on the glue or is the glue on the sand? And was the sand on his hands or were his hands in the sand? The glue in Rome. You said they didn’t use mass spec. Did they analyze it with FTIR?”

“I don’t think so. It’s cyanoacrylate. That’s as much as I know,” she says. “If we can try FTIR and see what molecular fingerprint we get.”

“Fine.”