Inception': The stuff that dreams are made of (Leonardo DiCaprio)

Leonardo DiCaprio is Cobb, an "excavator," who digs around in people's subconscious while they're catching some zzzzs. This act of infiltration is "not strictly legal"; the motive is not therapeutic but espionage and theft.

It's also not a solo operation. To do the job properly requires an "architect," basically someone to design an appropriate dreamscape, something vivid and detailed enough to keep the dreamer's defenses down. Depending on the complexity of the project, it might also require a "burglar," a "chemist" and preferably someone on the outside to administer a well-timed wake up call.

Cobb's partners include Arthur (Joseph Gordon-Levitt); a newbie, Ariadne (Ellen Page); Yusuf (Dileep Rao); and Eames (Tom Hardy). Their client, Saito (Ken Watanabe), wants more than access to a rival industrialist's grey matter; he requires Cobb to plant an idea in there that will dismantle an entire conglomerate.

As if that weren't hard enough, Cobb is also plagued with keeping his own demons at bay, in the form of an angry dead wife (Marion Cotillard). DiCaprio evidently hasn't got "Shutter Island" out of his system yet.A kind of meta-heist movie, "Inception" evokes Philip K. Dick's cerebral sci-fi, the exploration of alternate states of consciousness, memory and fantasy. But these are also Nolan's themes, familiar from the amnesiac noir of "Memento" and the many, varied mind-games practiced by the warring magicians in "The Prestige" as well as the psychological warfare between Batman and his adversaries (fans of that series will recognize several familiar faces popping up here).

"An idea is like a virus," says Cobb, and that idea too might have been born in Gotham City or in the rabid enthusiasm that greeted "The Dark Knight."

Like "Memento" and "The Prestige," "Inception" is constructed as a box of tricks. Ariadne (who helped Theseus slay the minotaur in Greek mythology) devises labyrinths that are also escape hatches, and that metaphor of the maze runs through "Inception," which is itself a puzzle to be navigated by filmmaker and audience alike.

In the course of probing his subject's subconscious, Cobb escorts him into a dream-within-a-dream-within-a-dream. If it's a little disappointing that each level plays out as a straight-up action thriller (this guy really should get out more), the rules of this game are delightfully devious.