In this true story of a 1970s London bank heist with major political ramifications, a group of burglars tunnel through to the basement of a bank, but the tunnel almost collapses on them. Their communications with one another, via walkie-talkies and ham radios, are overheard, and the police are notified. The police respond but don't find the robbers because they fail to look in the basement. The robbers steal the contents of the safety deposit boxes which contain compromising photographs and other evidence of wrong-doing by major politicians and business people. Before they can escape, however, their getaway car is stolen and the replacement truck gets stuck in the tunnel until a little boy, passing by the tunnel entrance, suggests that they let the air out of the tires and this helps them escape. After their escape they are tracked by the police as well as the powerful people they have inadvertently robbed.