THERE ARE two schools of thought about comic books. One is that they serve our hunger for folk-tale simplicity. The friction of passing time magnetizes these stories, making them attract elements of world religion: Superman, who began as part Golem, has (per Alex Ross) been illustrated to look like Jesus.

As for the second school of thought? That would be the thought that if it's not about guys in cool suits kicking ass, I don't want to hear about it.

Matthew Vaughn's Kick-Ass, hiding in the safety zone right down the middle of these two theories, should be a big hit. There's a ferment over the film on the Internet, and the amped-up violence will also sell. The sequence about a Robin-the-Girl-Wonder type getting the tar stomped out of her is something new. Generally, children don't get beaten up badly in the movies, and if there's anything we've learned over the years, it's that any new sensation will boost a film's box office, no matter what side of the moral line it inhabits.

Working from a comic-book series by silver-age cartoonist John Romita Sr. and writer Mark Millar, Kick-Ass starts us out with Dave (Aaron Johnson), a teen without qualities beyond masturbation and comic-book reading. He decides to become a costumed vigilante. He orders a lime-green scuba-diving suit and names himself Kick-Ass; on his first patrol, Dave gets squashed fast by bullies. The doctors who put him back together give him a metal skeleton. He's had enough nerve damage that he feels no pain.

Resuming his patrols, Dave encounters the genuine item: a graying Batmanesque figure, portly, with a biker's mustache. He is called Big Daddy (Nicolas Cage). His partner and beloved daughter is Mindy, known as Hit-Girl, played by Chloë Moretz, who was the wise little girl in (500) Days of Summer.

The two heroes are doing right what Kick-Ass does at an amateur level. Big Daddy and Hit-Girl have a large armory, a definite target and the good sense not to host a website. They're both zeroing in on the crime boss of the town, Frank D'Amico (Mark Strong), a savage in a penthouse who keeps (nice detail) the leathery, preserved head of one of his rivals in a vitrine near the elevator door.

Vaughn, a British director who did Layer Cake and Stardust, has the problem of disguising Toronto the Good as New York the Ugly during the street beefs. Johnson's studious lack of personality adds to the lack of a center: he's a D.C.-style blank alter ego in a Marvel-style movie. Big Daddy and Hit-Girl are the urgent part of the movie; they vanish when Dave narrates, telling us about his friends and the girl (Lyndsy Fonseca) he likes.

Cage is an actor who, once upon a time, took his stage name from a comic book, and he's in tune with the flamboyant mania of comics in his performance. He shows us the monstrousness underneath the mask: Big Daddy bent his daughter to the mission of climbing up walls and shooting people. Moretz's grit and oddly gravelly voice—she never seems annoyingly precocious—will make a star out of her. The scene in which Hit-Girl cleans up a hallway loaded with gunmen to Joan Jett's "Bad Reputation" might be some little girl's dream; there are plenty of bloody-minded little girls out there, and thank heaven for them.

But it's nuts to call Kick-Ass the next Watchmen, as some het-up critics are going to do. Vaughn uses the comic-book tropes wholesale, but he has no feeling for the romance or the mystery underneath them. The slamming violence and the dullard nom de guerres these obsessives picked for themselves are presumably meant to show a comic-book tradition at the end of a line. Cage carries all of this movie's ambiguity, but Kick-Ass is a film that makes you feel beat up afterward.

KICK-ASS (R; 117 min.), directed by Matthew Vaughn, written by Jane Goldman, Mark Millar and Vaughn, photographed by Ben Davis and starring Nicolas Cage, Chloë Moretz and Aaron Johnson, opens Friday countywide.

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