The widow of Captain Errol, youngest son of the Earl of Dorincourt, and her young son, Cedric, live in New York City in the early 1880's barely able to subsist. The earl, how heiress, commissions his solicitor, Haversham, to bring young Cedric from America to be trained for the title of Lord Fauntleroy. When they arrive at the castle, the mother (Dearest), wrongly accused of marrying for pecuniary reasons, is forced to live outside the castle while Cedric with his innocent and childish wit captivates the earl and wins the hearts of his royal guests. Haversham appears with a woman who claims that her son is the nearest relatives of Bevis, the eldest son, and she demands the title for him. When New York papers print the story with photographs, Cedric's friends--Dick, Hobbs, and Mrs. McGinty--journey to England to expose the conspiracy. The earl is overjoyed at the news, and there is a reconciliation between Dearest and the earl; all three live happily together in the castle.