When his mother dies, young Peter Ibbetson leaves Paris and his best friend, Mary, behind to live with a severe uncle in England. Years later, Peter is an architect with little time for women, until he begins a project with the Duke and Duchess of Towers. When Peter and the duchess become great friends, she reveals that she is Mary — but the duke soon suspects his wife of infidelity and challenges Peter to a duel, threatening the pair's second chance.