Mississippi Mermaid (French: La Sirène du Mississipi) is a 1969 romantic crime drama film written and directed by François Truffaut and starring Jean-Paul Belmondo and Catherine Deneuve.

Adapted from the 1947 novel Waltz into Darkness by William Irish, the film follows a tobacco planter on the island of Réunion who becomes engaged through correspondence to a woman he does not know.

It was remade in 2001 as Original Sin, directed by Michael Cristofer and starring Angelina Jolie and Antonio Banderas.

Louis Mahé, a wealthy tobacco plantation owner on the island of Réunion in the Indian Ocean, awaits the arrival of his bride-to-be, Julie Roussel, whom he has never met.

Explaining that her real name is Marion Vergano, she tells him of her sordid past; of her years in prison and association with a heartless gangster, Richard, who was with her on the Mississipi.

They buy a convertible and drive to Aix-en-Provence, where they move into a house and spend their days traveling the region and making love.

Louis and Marion flee to Lyon, but she grows dissatisfied with their fugitive existence and longs for a life of luxury in Paris.

As she pours him another glass of coffee, he reveals his knowledge of her plan, accepts his fate with no regrets, and expresses his love for her.

[4] In his review in The New York Times, Vincent Canby wrote that the film "defies easy definition and blithely triumphs over what initially appears to be structural schizophrenia.

"[10] Canby concluded: In Mississippi Mermaid, as in all of Truffaut's films, love leads only to an uncertain future that, at best, may contain some joy along with the inevitable misery.