Grade: A

The bottom line: With an action-packed plot and jarringly human characters, The Dark Knight is the perfect summer blockbuster.

There have been a lot of superhero movies this year. Iron Man and Hell Boy II were both heartfelt and humanistic, but the setting and the characters were always sharp reminders that this was a fantasy world — not your own.

What has always set Batman apart as a superhero is that he is completely human. He isn’t a mutant, he doesn’t possess super-human strength, and he can’t shoot anything out of his hands. Perhaps that’s Batman’s attraction to his loyal fan base, the reason he so easily transitioned from comic-book hero to big-screen action star: Batman proves that superheroes are thoroughly people. The Dark Knight takes that quality and creates a movie few, if any, superhero movies have ever done. It is believable.

The Dark Knight is set in a very human world. In the opening scene guns, grenades and good, old-fashioned treachery is utilized in a bank robbery. And those who wield these weapons aren’t from Hell or another planet; they’re human, and they die with a good shot to the head. It helps that much of the film was shot in our backyard of Chicago, including stunning, panoramic shots of the bridges along the Chicago River when the city evacuates to escape the bombings threatened by the Joker (Heath Ledger).

The action isn’t too shabby either. Whether it’s chasing the Joker in an 18-wheeler through the tunnels of LeSalle Street or battling in hand-to-hand combat, the film has variety, and gorgeous explosions. The plot is more crime-thriller than superhero flick. Tight, well-wrought and with plenty of turns (albeit, a few too many diversions), it’s also intelligent. The film asks what is the nature of good, the nature of evil and the nature of people, but never gives a single, hokey answer.

The casting is near-perfect and the acting is pretty killer. Heath Ledger has already received rave reviews and Oscar hype for his final role as the Joker. He’s sadistic, haunting and psychotic. Even with ghoulish makeup and without a back story, you don’t ever doubt that he is a man who “just wants to see the world burn.” The villains are always the hardest characters to make appear real, but it’s the little things that make Ledger’s Joker a standout, even against the likes of Jack Nicholson, who played the role in Tim Burton’s 1989 version. After a police interrogation, his trademark makeup is grossly smeared — proving that he, too, is only human, and a disturbed one at that.

Though Ledger is a standout, the performances by Gary Oldman (Lt. James Gordon), Michael Caine (Alfred Pennyworth) and Aaron Eckhart (Harvey Dent), with his always likable mix of sleaze and charm, shouldn’t be overlooked. But, whileChristian Bale’s performance as Bruce Wayne gave Batman real heart, his voice in the suit is too cartoonish for a film trying to go beyond its kitsch genre.

In the end, the movie is more about Ledger’s Joker than Bale’s Batman: the Joker’s character, not his actions, are what the whole movie is based around, and what Batman (and the audience) has to battle. What is the nature of evil?

Six Flags Great Adventure already released a rollercoaster based and named after the film. The “one-of-a-kind dark ride experience,” according to Six Flag’s Web site, may best sum up the film: “Venturing through demented hallways of twists, turns and hallucinatory images, [audiences/riders] are tormented by The Joker himself.”