She wears a tattered evening gown, she is young, beautiful - and dead. The body of a woman is found in a square in Montmartre. No one seems to know her or miss her. The perpetually grumpy Inspector Lognon assumes it's a classic case of a prostitute murder, while Maigret senses that things are quite different. Filled with compassion for her fate, he wants to learn more about the young woman's past, who wanted to start a new life in Paris. Maigret is convinced that this will lead him to the murderer. Maigret's 45th case takes place in the Parisian entertainment district of Montmartre.