In the late 1970s, Cockney crime boss Harold Shand, a gangster trying to develop into a property mogul, has big plans to find the American Mafia to bankroll his transformation into a derelict part of London to the venue for another Olympic Games. But a series of bombings goals his empire over the very weekend the Americans have been in town. Shand is convinced there is a traitor within his company, also sets out to eradicate the rat in vogue.