A British petty criminal lies to his son about his frequent prison terms by inventing honorable plausible explanations for his absences from home, but things get complicated when his son becomes a judge's assistant.

When Percy Brand (Sir Michael Redgrave), a habitual confidence trickster, keeps being sent down, he goes to great lengths to ensure that his son Colin (Jeremy Burnham) does not find out about his criminal past. But when Colin becomes an assistant to Judge Sir Edward Crichton (Robert Morley), who is about to try Percy for his latest escapade, Percy and his gang have to come up with a plan, to stop them meeting in court.—<[email protected]>