Cooper was enjoying this way too much. "I don't need round-the-clock protection," I said. "If this guy was obsessed with me, he wouldn't have stopped at one blow, any more than he would've if he was obsessed with Lexie. Everybody relax."

"Right," Sam said, after a moment. He didn't sound happy. "I think that's the lot." He sat down, hard, and pulled his chair up to his desk.

"She wasn't killed for her money, anyway," Frank said. "The five of them pool most of their funds--a hundred quid a week each into a kitty, to pay for food, petrol, bills, doing up the house, all the rest of it. On her income, that didn't leave much. She had eighty-eight quid in her bank account."

"What do you think?" Sam asked me.

He meant from a profiling angle. Profiling is nowhere near foolproof and I don't actually have much of a clue what I'm doing anyway, but as far as I could see, everything said she had been killed by someone she knew, someone with a hair-trigger temper rather than a well-nursed grudge. The obvious answer was either the kid's father or one of the housemates, or both.

But if I said that, then this meeting was over, at least as far as I was concerned; Sam would blow every gasket at the thought of me sharing a house with the odds-on favorites. And I didn't want that. I tried to tell myself it was because I wanted to make the decision, not have Sam make it for me, but I knew: this was working on me, this room and this company and this conversation, pressing subtly just like Frank had known they would. Nothing in this world takes over your blood like a murder case, nothing demands you, mind and body, with such a huge and blazing and irresistible voice. It had been months since I had worked like this, concentrated like this on fitting together evidence and patterns and theories, and all of a sudden it felt like years.

"I'd go with door number two," I said, finally. "Someone who knew her as Lexie Madison."

"If that's where we're focusing," Sam said, "her housemates were the last ones to see her alive, and they're the ones were closest to her. That puts them front and center."

Frank shook his head. "I'm not so sure. She was wearing her coat, and it wasn't put on her after she died--there's a slit in the front right side, perfect match to the wound. To me, that says she was out of the house, away from the housemates, when she got stabbed."