A very beautiful woman, Mary, is found dead, strangled, lying on a bed of straw in a stable close to a canal lock. Maigret was looking for her in connection with a jewel robbery. Since the murder was committed in Belgium, Maigret has been sent there by Interpol. The investigation has trouble getting under way in the very closed world of bargemen. Maigret has several suspects, all are moored in the canal and are waiting for the dead woman to talk, to point to her murderer so they can cast off. There's the "Boxer" who never climbed into a ring; there's also Willy, the dandy at the service of Sir Lampson and his launch, who will be the second victim; and finally Sir Lampson himself, a retired Colonel from the Indian Army and Mary's husband. Voices are raised, feelings start to run high, and in spite of Maigret forbidding it, the bargemen decide to cast off to save their cargoes and to escape from the killer. However, the murderer is the silent towman, Jean, who works for the barge "La Providence" and prefers the company of his horses. He would have been a man of position and wealth if fifteen years earlier he hadn't fallen hopelessly in love with a woman too fond of jewelry. Directed by Andre Chandelle, 2001, color. In French with English subtitles.