When Leonard Vole is arrested for the sensational murder of a rich, middle-aged widow, the famous Sir Wilfrid Robarts agrees to appear on his behalf. Sir Wilfrid, recovering from a near-fatal heart attack, is supposed to be on a diet of bland, civil suits—but the lure of the criminal courts is too much for him, especially when the case is so difficult.

The hunt is on to find the murderer of a wealthy glamorous heiress who is found dead in her London townhouse. Based on the short story by Agatha Christie.