9. Supergirl (1984)
Supergirl may not be Superman but she does deserve a mention in this list.
The 1984 Supergirl movie is probably one of the most amazing blunders in Warner Bros. and DC history. The film had similarities to 1978’s Superman: The Movie but was an abysmal take on the character, following Kara Zor-El on her path to recovering the lost Omegahedron. It featured the villainous Selena, a witch who had recovered the Omegahedron and was using it to take over the world. Unfortunately, this film suffered from speedy pacing, a bad story and a ridiculous ensemble of characters.
With the Superman franchise doing so well, Warner Bros. created this film to try expand on that universe. But after receiving terrible reviews from both critics and audiences, Supergirl was deemed dead on arrival once it hit theaters, so the studio decided to just stick with the Christopher Reeve Superman films. At the time, however, it seemed as if these movies were slowly starting to dwindle and wither away from the consciousness of film fans.