The movie follows two brothers, Nobby (Will Ferrell) and Art (Mark Wahlberg), who were separated at birth and adopted by different families. Nobby grows up in a loving family, while Art is adopted by a wealthy family but feels unloved and neglected. The two brothers meet by chance in London, and Nobby, who is a charming and charismatic football hooligan, convinces Art, a spy, to help him with a mission.