Supergirl is a 1984 British superhero film directed by Jeannot Szwarc and written by David Odell, based on the DC Comics character of the same name and serves as a spinoff to Alexander and Ilya Salkinds Superman film series. The film stars Faye Dunaway, Helen Slater as Supergirl, and Peter OToole, with Marc McClure reprising his role as Jimmy Olsen from the Superman films. He was the only actor to do so.
Kara ZorEl Helen Slater lives in an isolated Kryptonian community called Argo City, in a pocket of transdimensional space. A man named Zaltar Peter OToole allows Kara to see a unique and immensely powerful item known as the Omegahedron, which he has borrowed without the knowledge of the city government, and which powers the city. However, after a mishap, the Omegahedron is blown out into space. Much to the distress of her parents Simon Ward and Mia Farrow, Kara follows it to Earth undergoing a transformation into Supergirl in the process in an effort to recover it and save the city.On Earth, the Omegahedron is recovered by Selena Faye Dunaway, a powerhungry wouldbe witch assisted by the feckless Bianca Brenda Vaccaro, seeking to free herself from her relationship with warlock Nigel Peter Cook. Whilst not knowing exactly what it is, Selena quickly realizes that the Omegahedron is powerful and can enable her to perform real magical spells. Supergirl arrives on Earth and discovers her powers. Following the path of the Omegahedron, she takes the name Linda Lee, identifies herself as the cousin of Clark Kent, and enrolls at an allgirls school where she befriends Lucy Lane Maureen Teefy, the younger sister of Lois Lane who happens to be studying there. Supergirl also meets and becomes enamoured with Ethan Hart Bochner who works as a groundskeeper at the school. ........
Source: Wikipedia