Kick-Ass plays as both as homage to superheroes and the superhero movies that have swamped mainstream movies over the last few years, and as its own movie of that new genre in its own right. Those who are at all into masked heroes and other such geek-like things will get a kick out of the prolific references throughout. And those who are your more average movie goers will likely just kick back and enjoy the splendid action it has to offer in spades.
The movie is based on the comic book series of the same name by Mark Millar (who's also had his Wanted comic adapted into a big-budget movie). I have to admit I've never read it, but word is it's as profane and violent as you can get. Luckily, director Matthew Vaughn and his co-writer Jane Goldman (who also worked together in the same capacity on Stardust) have decided to keep those extremities intact for the movie version.
The result is indeed a plethora of violence and swearing, and most of that is courtesy of an 11-year-old purple wig-wearing young chick nicknamed Hit-Girl (played wonderfully by rising star Chloe Moretz). She's just one of many superhero wannabes who have surfaced ever since Dave Lizewski (Aaron Johnston) decided to don a custom green scuba outfit and call himself "Kick-Ass." Also getting in on the action are Big Daddy, the father of Hit-Girl (played by Nicolas Cage) and Red Mist (Christopher "McLovin'" Mintz-Plasse).
Kick-Ass is pretty much the perfect "fun time at the movies" movie. It provides everything a movie of its type should, but not only gives you enough but gives you more than you could ever want. Gunfights, fist-fights, chase sequences - all shockingly well choreographed - genuinely hilarious gags (both sight gags and in dialogue), a solid plot, and just about anything else you could want.