You are the crew of the HMS Defiant. One of you is planning a mutiny. The Mutineer's goal: to survive while the others attempt to discover you.
Players take on the role of one of the 8 crew members on the ship: Chaplain, Boatswain, Quartermaster, Surgeon, Navigator, First Mate, Master Gunner, or Cabin Boy. Roles are public knowledge, but the identity of the mutineer remains hidden. Over the course of two rounds, players try to discover the mutineer through discussion, accusation, denial, and special actions. The game ends with a vote to convict one player guilty of mutiny. If the mutineer is voted guilty, all the other players win. Otherwise, the mutineer wins.
Each role has unique abilities that may help reveal the mutineer or allow them to exert control over the the voting. Since any player could be the mutineer, an accusation could be helpful, or a clever attempt to re-direct suspicion elsewhere. Mutiny is a social game with a minimal rule set. The game instead relies on player discussion and interaction to drive the game.