UK, 1950. A gang of robbers led by the self-proclaimed George 'The Great' Brain (Sid James) rob a bank, stealing £50,000. However, due to a mix-up, they are pursued and caught by the police. He manages to stash away the money in a case in the trunk of a hollow tree, before he is collared. The gang are then sentenced to serve fifteen years in Wormwood Scrubs (HM Prison).