“I think we know.” He pulls off his gloves and tosses them into the nearby biohazard trash bag hanging on a metal stand. “It’s hard to imagine we’re talking about two different women who look similar, are about the same age, and both had on Converse sneakers and a Sara Bareilles concert T-shirt. And maybe the same type of sunglasses. And they appeared in the same part of Cambridge at the same time.”

“Even if they’re the same person that doesn’t mean we know who she is.” I’ll continue reminding him to be conservative even if he doesn’t listen.

“And the other thing the girls had squirreled away?” He picks up a roll of paper towels, tearing off several squares to wipe his face. “A pendant. A gold skull about the size of a quarter, like from a necklace. I’m thinking it came from the broken gold chain.”

“Where was it found?”

“They said on the path near the bike. Based on where they showed me, I’m thinking it was in the general area where the pieces of chain were.” He tosses the wadded paper towels into the bright red trash bag next, and I follow them with my used shoe covers.

“The woman I encountered earlier was wearing an unusual necklace shaped like a skull. It was gold and looked fairly substantial, not flat like a medallion but rounded with contours,” I inform him. “I noticed her flip it around to her back, tucking it into the back of her shirt when she rode across Quincy Street, heading into the Yard.”

“It’s gotta be her, and I’m not liking that you saw her twice right before she got whacked. I keep worrying that she’s got some connection to you, Doc.”

“I can’t imagine what it would be,” I reply. “I don’t believe I’d ever seen her before today.”

Then I tell him about my Internet searches for Elisa Vandersteel. I couldn’t find her in London or anywhere.

CHAPTER 28

THE DRIVER’S LICENSE COULD be fake,” he says. “These days technology makes it a piece of cake to counterfeit IDs that look like the genuine article.”

“It’s odd that whoever Elisa Vandersteel is she doesn’t seem to be on social media either,” I inform him. “What young person isn’t these days? And I came across nothing in the news about anyone with that name that might be her. But I only looked for a few minutes.”

“I agree it’s strange. Unless she had reason to stay below the radar.” Marino pulls down his white hood, patting dry his shiny head with paper towels. “Jesus, I’m sweating like a whore in church. Or she had a fake ID card, and there’s no such thing as an Elisa Vandersteel with that DOB and address. And maybe that’s why there’s no one with that name on social media.”

“Lucy’s working on it. Let’s see what she comes up with.” I tear open a packet of coveralls.