The story is about Dave Lizewski (Aaron Johnson), a geeky high school student from the U.S. that took place is known by everyone. Comics fan, takes the idea one day become a superhero, even without superpowers, yet took the hard training and did not even have a significant reason.
Like a good superhero, choose a new name, 'Kick-Ass', and buy clothes and masks to go to work in the fight against crime.
Here is stabbed by a pair of thugs and press after, leaving him hospitalized, his nervous system is disabled and does not hurt, his bones broken by trampling reinforced with metal parts so you can stand. All this left him with insensitivity to pain and resilience of a big surprise.
However, not easy to be a hero, it will be pursued by the masses and an unexpected enemy, some crazy Avengers, a 11-year-old girl was trained by his father's Hit-Girl (Chloe Moretz), his father, Big Daddy (Nicolas Cage) and "friends of war" is called Red-Mist (Christopher Mintz-Plasse).