A body and an open safe seem to suggest murder in the course of robbery but Maigret realizes that the case is not so simple as he uncovers bitterness and unhappiness in the lives of the suspects.
A successful and ruthless businessman is sure that someone is out to kill him and asks Maigret for protection. The Chief Inspector dislikes the man and disbelieves the threat but events force Maigret to think again.
Maigret takes a telephone call from an unknown man claiming to be pursued by assassins. When a murdered body is thrown from a car, Maigret is sure he has found the mystery caller.
Maigret finds a man wandering the streets who cannot speak and seems to have lost his mind. The Chief Inspector sets out to discover how the man came to be as he is.
A rough, prosperous barge owner survives being stabbed and pushed into the canal. As Maigret tries to discover the culprit, another man ends up in the canal. But this one is dead.
A malign postmistress is shot dead through her window and a schoolmaster is suspected of her murder. Maigret must wade through the lies of the villagers and their children to find the truth.
Maigret does not welcome a visit from one of his neighbours on Christmas morning but her tale of a little girl mysteriously receiving a present from Father Christmas intrigues him.