“I know one in a private collection.”

“The Hewlett’s was in private hands, too. Now it’s in public hands, and unless it gets to be in our hands soon-”

“Forget that one. The one I’m talking about is still in a private collection, because I saw it last night.”

She looked at me. “I know you went out last night.”

“Right.”

“But you didn’t tell me what you did.”

“Well, you can probably guess. But what I did first, what got me into the building, is I appraised a man’s library. A nice fellow named Onderdonk, he paid me two hundred dollars to tell him what his books were worth.”

“Were they worth much?”

“Not compared to what he had hanging on his wall. He had a Mondrian, among other things.”

“Like the one in the Hewlett?”

“Well, who knows? It was about the same size and shape and I think the colors were the same, but maybe they’d look completely different to an expert. The thing is, if I could get in there and steal his Mondrian-”

“They’ll know it’s not the right one because it’ll still be on the wall at the Hewlett.”

“Yeah, but will they want to argue the point? If we can hand them a genuine Mondrian worth whatever it is, a quarter of a million is the figure they came up with-”

“Is it really worth that much?”

“I have no idea. The art market’s down these days but that’s about as much as I know. If we can give them a Mondrian in exchange for a stolen cat, don’t you think they’d go for it? They’d have to be crazy to turn it down.”

“We already know they’re crazy.”

“Well, they’d also have to be stupid, and they couldn’t be too stupid if they managed to swipe the cat.” I grabbed her phone book, looked up Onderdonk’s number, dialed it. I let it ring a dozen times and nobody answered it. “He’s out,” I said. “Now let’s just hope he stays out for a while.”