SUICIDE SQUAD opens with an extended sequence detailing each character's incarcerations and transfer to Belle Reve Penitentiary. The sequence is set to pop music and each time a new character appears, his name and rapsheet appear on screen in bright neon colors.
Deadshot is an ex-military turned contract killer who once tried to kill the Batman, only for his daughter to place herself between him and Batman, defending Batman, and leading to Deadshot being arrested and harboring an intense hatred of Batman.
Killer Croc is a cannibal who lives in the sewers and works as a mucle-for-hire for other criminals. He was arrested by Batman.
El Diablo is a former gangster from a Los Angeles cholo gang who repented after he accidentally set his wife and children on fire, and is now a pacifist who refuses to use his powers.
Captain Boomerang is a mercenary who got busted by the Flash during a botched assassination.
Slipknot is also a mercenary and got caught by Batman.
Katana is not a criminal, but her late husband was a killer for hire, and she volunteers to work for the government to atone for his crimes.
Enchantress is an archaeologist working for the government, who is searching for evidence of ancient aliens when she touches a voodoo doll and gets possessed by a spirit witch.
Culminates with Harley Quinn, a psychologist who became infatuated with the Joker after he tortured her and ultimately became his girlfriend. The Joker actually likes Harley even though he treats her like shit. Batman busts a deal between the Joker and a weapons dealer, Monster T, and the Joker ditches Harley in order to escape. Batman brings both Harley and Monster T in.