Supergirl is a 1984 British superhero film directed by Jeannot Szwarc from a screenplay by David Odell based on the DC Comics character of the same name. It is the fourth film in the Superman film series, set after the events of Superman III (1983) and serving as a spin-off of the series. The film stars Helen Slater as Supergirl, along with Faye Dunaway, Hart Bochner, Peter Cook, Mia Farrow, Brenda Vaccaro, and Peter O'Toole, with Marc McClure reprising his role as Jimmy Olsen from the Superman films.
The film was released in the United Kingdom on 19 July 1984 by Columbia-EMI-Warner Distributors, and in the United States on 21 November 1984, but failed to impress either critics or audiences, to generally negative reviews from critics. It underperformed at the box office, grossing $14 million against a $35 million budget. Slater was nominated for a Saturn Award for Best Actress. The film's failure ultimately led producers Alexander and Ilya Salkind to sell the Superman film rights to The Cannon Group, Inc. in 1986.