Cast
- Josh Brolin as Jonah Hex: A disfigured bounty hunter. Prior to Brolin's casting, actor Thomas Jane petitioned the studio for the role, hiring a makeup artist to give him the appearance of Jonah Hex. Brolin initially hated the script, but changed his mind, growing to like its tongue-in-cheek tone.
- John Malkovich as Quentin Turnbull: The film's antagonist.
- Megan Fox as Leila: A gun-wielding prostitute and Jonah Hex's love interest.
- Michael Shannon as Doctor Cross Williams: The ringleader of a gladiator circus. The studio plans to have Williams in a recurring character in sequels to the film.
- Michael Fassbender as Burke: A bowler hat-wearing, tattooed, psychopathic Irishman and Turnbull's right-hand man. Fassbender likens his character to that of The Riddler and Malcolm McDowell's performance in A Clockwork Orange but mainly said he found his character when he tried on the derby bowler.
- Will Arnett as Lieutenant Grass, a Union soldier who enlists Jonah Hex as a bounty hunter.
Lance Reddick was seen in the trailer as an armourer of sorts who supplies Hex with his new weapons.