Fan Casting Ilya Salkind's Superman III (1983)

What if Ilya Salkind's treatment of Superman III was actually used for the final film? Before the credits roll, it's revealed that Lois has transferred out of Metropolis and is replaced by a young woman named Lana Lang and she and Clark take a liking to each other. It is then revealed through flashback that another being escaped Krypton, another young baby, a girl, who remains unnamed. She lands on Colu, the home world of Brainiac who adopts her. She grows up and Brainiac begins to show affection for her and asks her to marry him but she denies it and leaves for Earth. Here, she finds Clark Kent/Superman and they fall in love (they aren't related in this universe) and she becomes Supergirl. Brainiac eventually finds them and starts to wreck havoc on Earth which involves changing Superman's personality to make him unpredictable, going back in time to the dark ages and becoming a tyrant, and fighting in a pocket dimension against Superman and Supergirl. As well as the Man of Steel meeting the being from the 5th dimension, Mr. Mxyzptlk. [Poster by Peter Stults]