"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.

The mall surprised Justin. In his time, it had seen better years. In 1999, just a little after being rebuilt because of the 94 earthquake, it still seemed shiny and sparkly and new. Justin got there early. With his hair short, with the Cow Pi T-shirt and jeans and big black boots he was wearing, he fit in with the kids who shopped and strutted and just hung out.

He found out how well he fit when he eyed an attractive brunette of thirty or so who was wearing business clothes. She caught him doing it, looked horrified for a second, and then stared through him as if he didn't exist. At first, he thought her reaction was over the top. Then he realized it wasn't. You may think she's cute, but she doesn't think you are. She thinks you're wet behind the ears.

Instead of leaving him insulted, the woman's reaction cheered him. Maybe I can bring this off.

He leaned against the brushed-aluminum railing in front of the second-level B. Dalton's as if he had nothing better to do. A gray-haired man in maroon polyester pants muttered something about punk kids as he walked by. Justin grinned, which made the old fart mutter more.

But then the grin slipped from Justin's face. What replaced it was probably astonishment. Here came his younger self, heading up from the Sears end of the mall.

He could tell the moment when his younger self saw him. Himself-at-twenty-one stopped, gaped, and turned pale.

He looked as if he wanted to turn around and run away. Instead, after gulping, he kept on.

Justin's heart pounded. He hadn't realized just how strange seeing himself would feel. And he'd been expecting this. For his younger self, it was a bolt from the blue.

That meant he had to be the one in control. He stuck out his hand.

"Hi," he said. "Thanks for coming."

His younger self shook hands with him.

They both looked down. The two right hands fit perfectly. Well, they would, wouldn't they? Justin thought. His younger self, still staring, said, "Maybe I'm not crazy. Maybe you're not crazy, either. You look just like me."

"Funny how that works," Justin said.

Seeing his younger self wasn't like looking in a mirror. It wasn't because himself-at-twenty-one looked that much younger-he didn't. It wasn't even because his younger self wasn't doing the same things he did. After a moment, he figured out what it was: his younger self's image wasn't reversed, the way it would have been in a mirror. That made him look different.

His younger self put hands on hips.

"Prove you're from the future," he said.

Justin had expected that. He took a little plastic coin purse, the kind that can hook onto a key chain, out of his pocket and squeezed it open. "Here," he said. "This is for you." He handed himself-at-twenty-one a quarter.

It looked like any quarter-till you noticed the date. "It's from 2012," his younger self whispered. His eyes got big and round again. "Jesus. You weren't kidding."

"I told you I wasn't," Justin said patiently. "Come on. What's the name of that Korean barbecue place on… Reseda?" He thought that was right. It had closed a few years after the turn of the century.

His younger self didn't notice the hesitation. "The Pine Tree?"

"Yeah." Justin knew the name when he heard it. "Let's go over there. I'll buy you dinner, like I said in e-mail, and we can talk about things."

"Like what you're doing here," his younger self said.

He nodded. "Yeah. Like what I'm doing here."

None of the waitresses at the Pine Tree spoke much English. That was one reason Justin had chosen the place: he didn't want anybody eavesdropping. But he liked garlic, he liked the odd vegetables, and he enjoyed grilling beef or pork or chicken or fish on the gas barbecue set into the tabletop.

He ordered for both of them. The waitress scribbled on her pad in the odd characters of hangul, then looked from one of them to the other. "Twins," she said, pulling out a word she did know.

"Yeah," Justin said. Sort of, he thought. The waitress went away.

His younger self pointed at him. "Tell me one thing," he said.

"What?" Justin asked. He expected anything from What are you doing here? to What is the meaning of life?

But his younger self surprised him: "That the Rolling Stones aren't still touring by the time you're-I'm-forty."

"Well, no," Justin said. That was a pretty scary thought, when you got down to it. He and his younger self both laughed. They sounded just alike. We would, he thought.

The waitress came back with a couple of tall bottles of OB beer. She hadn't asked either one of them for an ID, for which Justin was duly grateful. His younger self kept quiet while she was around. After she'd gone away, himself-at-twenty-one said, "Okay, I believe you. I didn't think I would, but I do. You know too much-and you couldn't have pulled that quarter out of your ear from nowhere." He sipped at the Korean beer. He looked as if he would sooner have gone out and got drunk.

"That's right," Justin agreed. Stay in control. The more you sound like you know what you're doing, the more he'll think you know what you're doing. And he has to think that, or this won't fly.

His younger self drank beer faster than he did, and waved for a second tall one as soon as the first was empty. Justin frowned. He remembered drinking more in his twenties than he did at forty, but didn't care to have his nose rubbed in it.

He wouldn't have wanted to drive after two big OBs, but his younger self didn't seem to worry about it.

With his younger self's new beer, the waitress brought the meat to be grilled and the plates of vegetables. She used aluminum tongs to put some pork and some marinated beef over the fire. Looking at the strips of meat curling and shrinking, himself-at-twenty-one exclaimed, "Oh my God! They killed Kenny!"

"Huh?" Justin said, and then, "Oh." He managed a feeble chuckle. He hadn't thought about South Park in a long time.

His younger self eyed him. "If you'd said that to me, I'd have laughed a lot harder. But the show's not hot for you any more, is it?" He answered his own question before Justin could: "No, it wouldn't be. 2018? Jesus." He took another big sip of beer.

Justin grabbed some beef with the tongs.

He used chopsticks to eat, ignoring the fork. So did his younger self. He was better at it than himself-at-twenty-one; he'd had more practice. The food was good. He remembered it had been.

After a while, his younger self said, "Well, will you tell me what this is all about?"

"What's the most important thing in your life right now?" Justin asked in return.

"You mean, besides trying to figure out why I'd travel back in time to see me?" his younger self returned.