We choose water, and he hands us cold bottles from the refrigerator. We sit at the counter. Skylar presses her bottle to her forehead before she opens it. The house is stiflingly hot. The air conditioner must be broken. I can’t get over the feeling we shouldn’t be here.

Mr. Boyce turns his sad eyes to us. “Now, what can I help you with?”

“Well, it’s kind of a long story,” Skylar begins, “but a few weeks ago, Abbi and I found this old tree house down at the end of Marie Drive.”

Mr. Boyce drinks his coffee. His hand shakes, and I wish I could comfort him. Instead, I say, “It’s a dead-end street way out on the edge of town. What Mom calls the bad side.”

Mr. Boyce peers into his coffee cup, his shoulders hunched. He doesn’t say anything, he doesn’t ask questions. He doesn’t even look at us. He just waits for us to go on.

“We were reading the books on our summer list,” Skylar says, “and we saw these cars. A black SUV came first and then a gray Honda. A woman got in the man’s SUV, and they drove away together. They met there every Thursday and parked right under our tree house.”

“We didn’t know it then, but the woman who drove the Honda was Ms. Sullivan,” I tell him. “She always wore a disguise—a big straw hat and humongous black glasses.” I’m getting tearful again, so I let Skylar take over.

“We never saw the man at all,” she says. “He stayed in the SUV.”

Mr. Boyce sips his coffee and then stares into the cup as if he expects to read his fortune there. He still hasn’t asked a question or looked at either one of us.

“Then, last Thursday, they had a big argument,” Skylar says. Her voice rises, as if she’s afraid Mr. Boyce isn’t listening. “Ms. Sullivan got out and walked across the field into the woods. He didn’t go after her. He just let her go and then drove away.”

Skylar takes a deep breath like she has to force herself to go on. “We think the man in the SUV killed her.”

Mr. Boyce draws in his breath and stares at her as if he can’t believe what she’s just said. He looks like he’s about to say something, but he sips his coffee again instead.

Skylar turns to me. “Show him the pictures and videos, Abbi.”

I hand my phone to Mr. Boyce. Luckily I’d put all the tree house pictures into a special folder; he wouldn’t see the ones of Skylar and me wearing Ms. Freeman’s sexy clothes. We’d experimented with her makeup and posed in crazy positions, laughing ourselves silly. If Mr. Boyce saw them, I’d die.