The Enemy Within is a British show where contestants answer trivia questions for money (pounds) and whoever has the most money at the end of the show wins. But, there is one player called the Enemy, who, before the game, has all the answers given to him/her. That player will have to try and keep their identity secret from other players for the whole show. At the end, the players and audience votes on who they think is the Enemy. If the majority of players guess correctly, the Enemy gets no money and loses. However, if the majority of players guess WRONG, the Enemy wins all the money. If there is a tie on who the players believe is the Enemy, the audience's vote is final.