I won’t beat around the bush: The Dark Knight is tremendous, the movie of the summer by a wide margin. It brings a depth to the superhero genre that I wouldn’t have thought possible, at least not from any filmmakers with a profit motive.

But then, The Dark Knight isn’t like any other superhero movie you’ve ever seen. This is not the stuff of brightly colored storybooks produced for children, with tales of pure-hearted heroes conquering banally evil villains. Nor is it an excuse for the special effects guys to show off the new tricks they’ve learned on their computers since last summer. It’s not even the Frank Miller graphic novels of the late 1980s from which it takes its title, though that’s where its spirit lies. (And perhaps those stories of a 50-year-old Batman, bitter at his failures and the impossibility of making a difference in the world, indicate where this new film series is headed.)

Director Christopher Nolan (Memento), who also wrote the film in collaboration with his brother Jonathan, has deconstructed the Batman canon, stripped it to its essentials and squeezed it to extricate its pulp. He looks at the character and asks, how would someone like this think and behave in the real world, like the one we live in? And how would that world be changed by having someone like him in it?

Don’t let me scare you off entirely: Nolan is still making a big-budget, special-effects action movie here. The Dark Knight gets your adrenaline racing from the very beginning (in a sequence that includes a showy bit for Cheektowaga native William Fichtner as a bank manager who isn’t about to cower in a corner when his bank is robbed) and seldom lets up for two and a half hours. Brilliantly photographed and edited, with a terrific score, it’s a considerable step up from its predecessor, the sometimes stodgy Batman Begins, which in retrospect was just laying the groundwork.

But wowing ’em in the cheap seats is clearly the compromise Nolan was willing to make to get to do the story he wanted. The closest the movie gets to dull is a protracted sequence in Hong Kong, though even that has such spectacular photography that I didn’t mind the plot briefly grinding to a halt. (The film was shot with six IMAX sequences, which is how I saw it, though you probably won’t lose much seeing it in a normal-sized theater.) And more often than not the action is well integrated into the film’s storylines.

With more than a few metaphorical references to life in post-9/11 America, The Dark Knight is a film about corruption. As must inevitably happen to someone obsessed with eradicating crime, Batman finds that the more he fights it, the more of it he sees. Gotham City is beset by vigilantes, less wealthy and capable than he, who don homemade bat masks but generally cause nothing but problems. (Call them WannaBats.) And the real criminals seem to be rising to his level, as if his accomplishments pose a dare to them.

Chief among these is the Joker (Heath Ledger). This is a good point to mention that you need to forget everything you remember about Batman and his milieu: the comic books, the TV series, the Tim Burton movies. If Ledger’s performance were the only thing The Dark Knight had going for it, the film would still be a must-see. Nolan strips the character of his more implausible attributes to get at his essence, a sociopathic lunatic who randomly and sloppily smears white paint on his face to cover scars that evince a horrifying past that is a mystery to us. He is not a clown but a brutal terrorist determined to bring everyone and everything to the lowest level: When he laughs, no one laughs with him.

How good is Ledger? You almost need a new vocabulary. It’s a performance that will be remembered in the same ways we remember Marlon Brando in On the Waterfront or Dustin Hoffman in The Graduate. He’s like Bette Davis at her best, and his Joker is as genuinely frightening a character as I’ve ever seen in a movie. I could only think to compare it to Anthony Hopkins in The Silence of the Lambs, if you remember seeing Hannibal Lecter before he was diluted by endless repetition and parody. I don’t think that Ledger’s is a performance that will be diminished by time, and you can’t help but come away from The Dark Knight saddened that, after a brief run comprising mostly the kind of second-rate films that begin a career, his ended just at a point when he took such an astonishing leap forward.

That Ledger doesn’t blow everyone else off the screen speaks well of the rest of the cast as well as of Nolan’s work in keeping his film balanced—a lot of directors graced with a performance this mesmerizing would rebuild their film around it. Maggie Gyllenhaal (thankfully replacing Katie Holmes), Aaron Eckhart, Michael Caine, Gary Oldman, and Morgan Freeman are all first-rate. As Batman/Bruce Wayne, Christian Bale has a less showy part, though I suspect Nolan will challenge him more in the next film. And on the basis of this, I can’t wait to see where he takes the character next.

A note: The Dark Knight may be rated PG-13, but only because the MPAA doesn’t want to diminish the box office potential of what is likely to be the top grossing movie of the year. It is by no means appropriate for young children.