Dave goes to the museum to see an artifact called "The Sides of Purity" and the villain Hidden steals it, he learns Hidden use the artifact to reawaken his grandfather's evil side and turning him to "Father Abyss."
Will Kick-Ass and Justice Forever will stop this threat?
- Dave Lizewski/Kick-Ass: A young hero and member of the Justice Forever. He learns that he and Jone is more alike, despite their is age differences.
- Mind McCready/Hit-Girl
- Jone Witton/Couragous (portrayed by Alex Russell): A young hero ressembles DC Nightwing and one of the heroes from Hidden Evil, he learns about the Side of Purity and tells Dave that his grandfather the one who defeated Father Abyss.
- Doctor Gravity
- Lieutenant Stripes
- Battle Guy
- Insect Man
- The All-Seeing-Eye
- The Enforcer
- Father Abyss (portrayed by Neil Ross): The main antagonist of the film and Hidden's grandfather, once a dictator for a unknown country and enslaving many people in the great war. Until, the day of a man using the Sides of Purity against him and making forget of being evil. Awaken by his grandson, he thanks him and assemble all the villains of the world. Cruel, sadistic and very intelligent, he has power to awaken the darkness of anyone and making them serve him as demon-like servants. Defeated by Kick-Ass and Courageous with Hidden's help, he dies and falls into the underworld.
- General Zin: One of Father Abyss's follower, Father Abyss revived his youth (25 years old) again and commands the Creeplings army.
- Ms. Mamba: One of Father Abyss's follower, Father Abyss revived her youth (25 years old) again and once again as "Assassin of Night".
- The Hammer
- Hidden: Minor antagonist, a former high school outcast and leader of the Forsaken, he learns about the Sides of Purity and re-awaking his grandfather's evil side. He is betrayed by his grandfather and his mask is removed, revealing his acid burnt face and spends the whole time of film finding his grandfather's weakness. He dies from the injury from Father Abyss.
- The Creeplings: Father Abyss's servants and people who transformed into a Creeplings, mostly villains who were at the ceremony of Father Abyss's return. Even, the Hidden's The Forsaken group is turn into Creeplings.
- Deadly Hair
- MK Gary
- Father Abyss is most terrified villain of the film series. He so feared, he was consider the "Devil" and people were scared of his present. He is the first villain of history to have powers granted by demon and promise him he'll turn the world of chaos. Before and now, his followers will chant his name and rally new comers to worship him.
- Kick-Ass is the only few immune to his powers.
- The world started to fall a part of Father Abyss's invasion, World Leaders are powerless to stop him and he killed them off.
- Jone's grandfather defeated Father Abyss, now he and Kick-Ass must take this task.