Having lost his memory due to serving in World War I, Gaston has spent the past 15 years in a psychiatric hospital. Due to his large disability pension fund, several families claim him as their missing son. Gaston is introduced to the Renaud family by the Duchess Dupont-Dufort and her lawyer. The Renaud family attempt to revive Gaston's memory with stories of his past, but he is apalled by some of the things he hears and dislikes the man he is supposed to be.