String theory postulates that - among other things I won't go into because this is the only thing I know about string theory - ours is but one of many universes. Furthermore, the future is continually fracturing into an infinite number of alternative universes.

'NEXT' - Nicolas Cage is the man with special cognitive abilities who is brought in to help the FBI thwart a nuclear terrorist threat in 'Next.'. CNS Photo courtesy of Joseph Lederer.

In one of them, "Next," yet another adaptation of a Philip K. Dick tale, is the swift, nifty, semi-sci-fi thriller it's supposed to be. In this one, it comes pretty close. Cris Johnson (Nicolas Cage) is a small-time Las Vegas magician who occasionally throws real magic into his act - or at least, what looks like magic: He was born with the ability to see up to two minutes into his future. If he doesn't like the looks of things, he can alter his actions, and thus change ... everything. As you can imagine, this comes in handy at blackjack.

Only for low stakes, though; he's living below the radar and wants to keep it that way. But he's come to the attention of three factions: the casino, which is getting steamed at his constant winning; the FBI, which needs his help in locating a loose nuke some terrorists have smuggled into L.A.; and those very terrorists themselves.

He's also brought himself to the attention of Liz (Jessica Biel), a young woman who, for some reason, he envisioned at a diner far in advance of his usual two-minute range. After they hook up - in a charming scene, he views the negative results of approach after approach, until he finds one that works - they're off to the Grand Canyon, where she teaches young Indian children. There, all hell sort of breaks loose. In one reality, anyway.

The FBI is there, led by on Callie Ferris (Julianne Moore, who plays but one note - tough, no-nonsense - throughout, but since it's Julianne Moore, you think that's one tough, no-nonsense FBI agent). The terrorists, who want to assassinate Cris because they know the FBI needs him, are there, too. But it's not easy to capture, much less kill, someone who's always 120 seconds ahead of the game, and "Next" has such mind-warping fun with Cris' devising various futures that you don't even notice that in none of them do some rather important elements of the plot make sense.

Such as: How is seeing two minutes into the future going to help the FBI find the nuke? And what do the terrorists - generic, off-the-shelf '80s Eurotrash, to a man and woman - want, anyway? If it's their aim to blow up L.A., why don't they just go ahead and do it?

You can't really say "no matter" to such annoyances, but in this case "little matter" is acceptable, as director Lee Tamahori ("Die Another Day") moves things along lickety-split and has a whale of a time doing so. Cage plays Chris as hangdog and weary, perhaps psychically spent from forever having to select which future to pursue. (In one inspired scene, he peels off multiple versions of himself in order to investigate the dangers in various possible pathways through a terrorist-riddled ship.) Biel seems like someone worth pursuing through any number of realities.

Not overly ambitious, "Next" nonetheless keeps you thinking, guessing and entertained. In some universe there's probably even an explanation for Peter Falk's folksy cameo. Not in this one, though. Not now, and, I predict, not two minutes from now.