How do I know? he wrote. I've told you twice now-I know because I am you, you in 2018. It's not X-Files stuff-it's good programming. The show still ran in endless syndication, but he hadn't watched it for years. He went on, Believe me, I'm back here for a good reason, and sent the e-mail.

Again, he waited. Again, the reply came back fast. He imagined his younger self eyeing the screen of his computer, eyeing it and scratching his head. His younger self must have been scratching hard, for what came back was, But that's impossible.

Okay, he typed. It's impossible. But if it is impossible, how do I know all this stuff about you?

More waiting. The hell with it, he thought. He'd intended to broil lamb chops, but he would have had to pay attention to keep from cremating them. He took a dinner out of the freezer and threw it into the tiny microwave built in above the stove. He could punch a button and get it more or less right. Back to the computer.

"You've got mail!" it said once more, and he did. I don't know, his younger self had written.

How do you know all this stuff about me?

Because it's stuff about me, too, he answered. You don't seem to be taking that seriously yet.

The microwave beeped. Justin started to go off to eat, but the PowerBook told him he had more mail. He called it up. If you're supposed to be me, himself-at-twenty-one wrote, then you'll look like me, right?

Justin laughed. His younger self wouldn't believe that. He'd probably think it would make this pretender shut up and go away. But Justin wasn't a pretender, and didn't need to shut up-he could put up instead. Right, he replied. Meet me in front of the B. Dalton's in the Northridge mall tomorrow night at 6:30 and I'll buy you dinner. You'll see for yourself. He sent the message, then did walk away from the computer.

Eating frozen food reminded him why he'd learned to cook. He chucked the tray into the trash, then returned to the bedroom to see what his younger self had answered. Three words: See you there.