A writer tells a crowd in a café about a woman he knows, who once fell deeply in love with a desperate, compulsive gambler. Also known as Affair in Monte Carlo, the film is based on a novella by Stefan Zweig.

At the beginning of the 20th century, in a casino on the Riviera, Marie Collins-Brown, an irreproachable woman, lives with Anton, an incurable gambler, and experiences the most intense 24 hours of her life. In trying to save him, she becomes chained to a demon. Twenty years later, this same woman, who had shut herself up in silence, confides her secret to a teenager revolted by his mother’s bad behaviour…