The movie tells the story of a shoe shiner who tries to save an African boy who has illegally immigrated in the French port of Le Havre. The protagonist, Marcel Marx, is a former bohemian writer turned shoe shiner, married to Arletty. The two elderly spouses lead a modest life in a poor neighborhood of Le Havre. One day Marcel meets Idrissa, a black boy who has just arrived from Africa and is wanted by the police because he is an illegal immigrant. He decides to help him and hide him in his home until he can raise the money necessary to pay for the boy to travel as an illegal immigrant across the Channel to London, to reunite him with his mother. At the same time, the protagonist has to deal with the hospitalization of his wife, who is suffering from an illness deemed incurable by doctors.