The Lost Daughter is a 2021 psychological drama film written and directed by Maggie Gyllenhaal in her feature directorial debut, based on the novel of the same name by Elena Ferrante. The film stars Olivia Colman, Dakota Johnson, Jessie Buckley, Paul Mescal, Dagmara Domińczyk, Jack Farthing, Oliver Jackson-Cohen, with Peter Sarsgaard, and Ed Harris. Colman also serves as an executive producer on the film. The lead character of Leda is borrowed from the W. B. Yeats poem Leda and the Swan, which is in turn based on Greek mythology.

The Lost Daughter had its world premiere at the 78th Venice International Film Festival on September 3, 2021, where Gyllenhaal won the Golden Osella Award for Best Screenplay. It began a theatrical limited release in the United States on December 17, 2021, prior to streaming on Netflix on December 31. The film received acclaim from critics.