- Allura In-Ze (Single appearance)
- Zor-El (Single appearance)
- Superman (Mentioned only)
- Nigel (Single appearance)
- Mr. Danvers (Single appearance)
- Lois Lane (Mentioned only)
- Binary Chute
Kara Zor-El came from the transdimensional world of Argo City, which has survived the destruction of its home planet Krypton. When Kara's mentor Zaltar allowed her unauthorized use of the city's power source the Omegahedron as something she could experiment with, Kara lost control of it and it fell to Earth, falling into the hands of a power-hungry witch named Selena. Kara used a binary chute to travel to Earth, appearing as Supergirl in order to track down the Omegahedron and disguising herself as a prep school student named Linda Lee, a cousin of the Daily Planet reporter Clark Kent. Kara eventually crosses paths with Selena, who is already using the power of the Omegahedron to build herself a fortress from which she could control the world. Selena casts Kara into the Phantom Zone, from which no Kryptonian could ever break free. However, Kara finds Zaltar, who has been sentenced to the Phantom Zone for stealing the Omegahedron, who now risks his life to help the young Kryptonian break free from the Zone. Kara returns to Earth to battle Selena and ultimately succeeds in defeating her, retrieving the Omegahedron and bringing it back to Argo City.
- Helen Slater as Kara Zor-El/Linda Lee/Supergirl
- Faye Dunaway as Selena
- Peter O'Toole as Zaltar
- Mia Farrow as Allura
- Maureen Teefy as Lucy Lane
- Hart Bochner as Ethan
- Peter Cook as Nigel
- Marc McClure as Jimmy Olsen
- Brenda Vaccaro as Bianca
- No special notes.
- The movie was originally produced by Warner Bros. Studios, but was given over to TriStar Pictures for its theatrical release due to the lack of success with Superman III
- An official novelization and a tie-in comic were published by Warner Books and DC respectively.
- Characters from Supergirl (Movie)
- Other things related to Supergirl (Movie)
- Movie Gallery: Supergirl (Movie)