A small-time crook has been murdered on the island of Porquerolles, the night after boasting of his ‘friend’ Maigret in a crowded bar. Chief Inspector Maigret is glad to leave rainy Paris to investigate the crime in the sunshine of the island, accompanied by a Scotland Yard detective studying French detection methods. But on Porquerolles they find no one with an obvious motive. Is someone trying to get at Maigret, or is the murderer involved in a more sinister conspiracy?..