There can’t be too many Holly-wood blockbusters in which the main characters spend three-fourths of the film asleep on an airplane. See, already “Inception” is unique.

Dreaming and movie-watching: two activities during which we witness projections of our hopes, wishes and fears (sometimes in 3-D). Dreams are a natural subject for film — one of the best movie subjects, in many ways.

It was inevitable that director-trickster Christopher Nolan should make a movie based on dreaming. With the puzzle film “Memento” and the ingenious “Dark Knight” to his credit, Nolan has already proved his interest in creating logic-twisters (and he made a movie called “Insomnia,” which ought to fit in here somewhere).

Nolan’s “Inception” is engrossing and gimmicky, a series of big-movie set-pieces with some genuinely haunting moments. The writer-director creates his own rules for his wacky premise, and then plays by them — I think.

Leonardo DiCaprio, still betraying no sense of humor (and needing none, in this role), plays Dom Cobb, a specialist in a certain corner of corporate espionage: He has the ability to induce deep dream states and extract secret information from the dreamer.

For much of the movie we are seeing those dreams, within which Dom and his team of experts operate. The big job involves a business tycoon (Ken Watanabe) who wants to plant a suggestion in the mind of a rival (Cillian Murphy) to break up the latter’s corporate empire.

Dom will enlist, in old- fashioned “Seven Samurai” style, his team of dream-weavers: Joseph Gordon-Levitt and “Juno” star Ellen Page among them, with Michael Caine popping by as a mentor. Tom Hardy is a particular standout as a droll chameleonlike “actor” in these dreams.

The dizzying part of this premise, which Nolan merrily invents with the zest of a kid toying with the world’s most complicated ant farm, is that the big sleep will involve different levels of dreaming, each one going deeper than the next.

Thus a crazy, elaborate set-up that puts all the main characters asleep on an airplane while they drop through levels of a giant shared dream: a rainy cityscape that looks like a Hong Kong action picture, a luxury hotel that might be out of a Stanley Kubrick movie, a snowy Alpine hillside (surely a rehearsal for the next James Bond film), and, finally, a computer-generated building where Dom’s worst nightmare awaits.

The dreams are also nightmares because Dom “projects” his own subconscious anxieties, most of which take the form of his ex-wife (Marion Cotillard).

And Nolan is so good at invading your subconscious mind, you might find yourself deciphering why the song “Je ne regrette rien,” sung by Edith Piaf, is repeatedly used in the film as a kind of trigger, and Marion Cottilard played Edith Piaf in the movie “La vie en rose,” which might suggest that her character is controlling certain aspects of the movie we’re watching… .

Or not. But Nolan makes you crazy thinking about stuff like that, once he gets inside your head.

I haven’t quite convinced myself that “Inception” is more than a skillfully-played con game — but even if that’s all it is, well, what a con game. You don’t dare take your eyes off the thing.