“Where they’re sent from. Lucy’s explained it. Having access to Dr. Self’s e-mail made it possible to trace the IP address of the Sandman. Just more proof she doesn’t care. She could have traced the IP address herself or gotten someone else to do it. But she didn’t. It probably never entered her mind. It traces to a domain in Charleston, specifically, the port.”

“This is most interesting.”

“You’re so wide open and effusive, Paulo.”

“I’m not sure what you mean by that. ‘Wide open and effusive’?”

“Lucy talked to the port’s IT, the guy who manages all of the computers, the wireless network, and so on,” Benton says. “What’s important, according to her, is the Sandman’s IP doesn’t correspond to any MAC at the port. That’s the Machine Address Code. Whatever computer the Sandman is using to send his e-mails, it doesn’t seem to be one at the port, meaning it’s unlikely he’s an employee there. Lucy has pointed out several possible scenarios. He could be someone in and out of the port—on a cruise ship, a cargo ship—and when he docks, he hijacks the port’s network. If that’s the case, he must work for a cruise ship or cargo vessel that’s been in Charleston at the port whenever he’s sent Dr. Self e-mails. Every one of his e-mails—all twenty-seven that Lucy found in Dr. Self’s inbox—were sent from the port’s wireless network. Including this one she just got. The woman in the copper tub.”

“Then he must be in Charleston now,” Dr. Maroni says. “I hope you have the port under surveillance. This may be the way to catch him.”

“We must be careful, whatever we do. Can’t involve the police right now. He’ll be scared off.”

“There must be calendars for cruises, for cargo ships. Is there an overlapping of those dates and when he sent e-mails to Dr. Self?”

“Yes and no. Some dates of a particular cruise ship—and I’m talking schedules for embarking and debarking—do correspond with date stamps on the e-mails he sent. But some don’t. Which makes me fairly certain he has some reason to be in Charleston, possibly even lives there, and gets access to the port’s network by perhaps parking very close to it and hijacking it.”

“Now you’re leaving me,” Dr. Maroni says. “I live in a very old world.” He lights his pipe again, and one reason he enjoys a pipe is the pleasure of lighting it.

“Analogous to driving around with a scanner and monitoring people on cell phones,” Benton explains.

“I suppose this isn’t Dr. Self’s fault, either,” Dr. Maroni ruefully says. “This killer has been sending e-mails from Charleston since last fall, and she could have known it and told someone.”