"Other obligations." Franck scratched a corner of his mouth. "I'd grown ambivalent about the relationship. For one thing I came to learn that Elise has a drinking problem. Nothing chronic, but she binges. My mother has a problem in that area and I've seen how it's affected her. Secondly, I prefer to date women my own age. I'm not claiming to be some kind of big-time player, but right now there's someone I'm involved with. She knows nothing about Elise and I'd like to keep it that way. I'm deeply sorry Elise is dead, I couldn't feel worse, she did a lot for me. But I'm really nervous about my personal life going public. That would be hell."

"No reason for your girlfriend to know, unless she's your alibi."

Franck's eyes widened. "I need an alibi?"

"Let me give you some--I guess you'd call them parameters--for the period of Elise's death."

As Milo outlined the time frame, Franck's shoulders loosened almost immediately. His grin was Christmas-morning bright, a kid in a room full of presents.

"During that entire time, I wasn't even in L.A., I was in Palo Alto for a series of research meetings with Professor Milbank--Professor Seth Milbank. He's conducting research at Stanford that might conceivably relate to mine. Professor Moon--my advisor, Professor Norman Moon--thought it would be a good idea for the three of us to sit down face-to-face and discuss possibilities. Professor Moon has travel money on his grant so we flew up. Feel free to check my plane tickets and my hotel reservation. I'd show you restaurant receipts--we ate out every meal--but Professor Moon paid for everything with his business card."

Milo said, "Tickets and hotel sound like a good start, Trey."

The young man slid off the sofa bed, retrieved his laptop from the floor, held the computer like a glockenspiel, and typed while standing.

Seconds later he showed us an online travel site screen.

Four-day stay at the Palo Alto Sojourner Inn, incoming and outgoing flights on Southwest.

"Satisfied?" said Franck.

"Four days," said Milo. "That's a lot of meetings."

"We made a side trip to Berkeley to confer with Professor Rosen."

Milo phoned the hotel, spoke with the desk, hung up. "Looks like you're cleared, Trey. Unless you've figured out how to be in two places simultaneously."

"Not yet, but maybe one of these days," said Franck.

"You're working on that?"

"Wait long enough, Lieutenant, and everything happens."

We left the shabby building, nearly collided with a helmeted student speeding up the footpath on a skateboard.

"Hey, watch it!"

Milo said, "Put more time into your physics homework."

"Huh?"

"Plotting trajectories, pal. Yours sucked."

The kid stared, waited until Milo's back was turned before flipping us off. Back in the car, I said, "Fish-and-chips?"

"Something's off with Franck but I can't pinpoint it."

"There's a minuscule speech delay," I said. "Like a machine processing."