Cityscapes fold onto themselves. Hotel hallways tumble upside down. A son tries to make amends with his father by breaking into a snowbound fortress straight out of a James Bond movie.

Behold the spectacle of “Inception,” a brainy puzzle-box of an adventure from writer/director Christopher Nolan. Underneath its blockbuster visuals, “Inception” is a surprisingly personal story of one man’s grief, told within dreams within dreams within dreams. Explosions and gunplay are added free of charge.

The less you know about the plot, the better, and anyway, it would take several paragraphs to describe the premise entirely. Leonardo DiCaprio plays Dom Cobb, the leader of a team who can access and manipulate people’s dreams in order to steal information. Ken Watanabe (“The Last Samurai”) plays a businessman who asks Dom to implant an idea into the mind of a rival businessman (Cillian Murphy). The technique, known as Inception, has supposedly never been accomplished, and Dom can’t keep memories of his ex-wife, Mal (Marion Cotillard) out of his head long enough to plan a proper con.

Enter Ellen Page (“Juno”) as a young architect who asks all the important questions about Inception and Dream Stealing. The film spends most of its first half explaining the process and rules of entering people’s minds. Nolan stacks this lecture series with some impressive visuals, including an incredible scene where Page’s character learns how to manipulate the Paris cityscape from within her mind.

“Inception” needs this long introduction because the second half of the film throws Dom’s team (which includes standouts Joseph Gordon-Levitt and Tom Hardy) into the mind of their intended mark. Successful inception requires the team to enter dreams within dreams, diving further into the subconscious (and to places where Mal can further manipulate guilt-stricken Dom).

It all sounds a bit confusing, but Nolan leaves lasting visual cues in various dream states to keep the audience along for the ride. “Inception” is much more straight-forward and easier to follow than, say, Nolan’s previous brain-bending gem, “Memento,” and the occasional hazy moment only furthers Dom’s increasingly central conflict with Mal.

DiCaprio and Cotillard do exquisite work in their scenes together, good enough to even forget the spectacular folding buildings and zero-gravity gunfights going on around them. Those action scenes, however, will probably encourage repeat business from “Matrix” fans in need of a good mind-trip.

Nolan has proved his visual prowess in his “Batman” movies, but with “Inception,” the director has borrowed and tweaked from a number of sources to concoct a wholly original blockbuster experience. He even gets around the whole “lack of tension” problem that can plague stories taking place within dreams and false realities. Without giving too much away, the characters in “Inception” definitely don’t want to be killed within any realm of the dreamworld.

Much will be discussed about the ending, and more generally, about whether “Inception” is more than just a stylistic lark. To me, “Inception” thrives in the quiet scenes between Dom and Mal, as well as the interactions between team members, marks, clients, etc. Even characters limited to a couple of scenes have an important role to play in this puzzle.

Of course, I’ll take those spectacular action sequences too, most notably the wild zero-gravity sequence involving Gordon-Levitt and a few dizzy dream goons. “Inception” is so tightly plotted and executed that you can’t help but admire Nolan’s expertise, even if film scholars eventually dismantle the story’s logic.

Several days after seeing “Inception,” I’m still thinking about it. I came out of the theater convinced I knew what the final scene meant to the entire film. Now I’m almost convinced the other way. Contrary to what some have said, “Inception” is an easy movie to understand on first viewing. That said, it’s also something audiences will want to be seeing again and again for a long time.

Grade: A