Having lost his memory through service in the First World War, Gaston has spent the last 15 years in a psychiatric hospital. Over this time, his disability pension has grown into a large sum of money and he attracts the attention of several families, who each claim that Gaston is their missing son. The philanthropic Duchess Dupont-Dufort has looked after Gaston's money during his time in hospital. She and her lawyer intend to introduce Gaston to a wealthy family who live in the country. Gaston could be Jacques, the son of Madame Renaud and brother of Georges Renaud, married to Valentine. The Renaud family are ready to revive Gaston's memory with stories of his past. Gaston is appalled by some of the things he hears and takes an immediate dislike to the man he is supposed to be. But is he really Jacques Renaud?