* ActingForTwo: Christopher Reeve in the junkyard fight.
* BTeamSequel: To the Creator/RichardDonner-helmed ''Film/{{Superman}}'' and (more or less) ''Film/SupermanII''.
* CaliforniaDoubling: The movie was shot in Calgary and High River, Alberta. Calgary doubled for Metropolis, while High River doubled for Smallville. This continued the trend from the last two films. In fact, the opening to the film takes place in downtown Calgary, as you may notice from the buildings.
* MoneyDearBoy: In his autobiography, Creator/RichardPryor admitted that he thought the screenplay for this movie was terrible and he only accepted the role because he was offered $5 million for it.
* OldShame: Creator/ChristopherReeve felt so ashamed about this movie that he swore he'd never play Superman again. It took lots of persuasion to bring him back for ''Film/SupermanIVTheQuestForPeace'', which sadly didn't turn out much better.
* {{Promoted Fan|boy}}girl: Annette O'Toole admitted in an interview for the documentary ''Look, Up in the Sky!'' that she loved reading ''Superman'' comics as a child, and preferred Lana Lang to Lois Lane.
* RefittedForSequel: The scenes in which Superman straightens the leaning tower of Pisa and then leans it back in the end were originally planned for ''Film/SupermanII''.
* RetroactiveRecognition: So Lana Lang [[CastingGag grew up to become]] ...[[Series/{{Smallville}} Ma Kent!]] Really, Annette O'Toole played Lana Lang here and (unbeknownst to the producers of the TV show) Martha Kent to Tom Welling's Clark.
* TechnologyMarchesOn: In one scene, a computer teachers says you can't do two things at once on a computer. Modern-day computers do multiple things at one time as a matter of course.
* ThrowItIn: Reportedly, Creator/RichardPryor was encouraged to ad-lib a lot, but because he was a Superman fan, he mostly stuck to the script.
* WhatCouldHaveBeen:
** According to Ilya Salkind, the original script was going to involve Comicbook/{{Brainiac}} and Mr. Mxyzptlk (who would have played by Creator/DudleyMoore) teaming up against Superman, who would also meet his cousin, Comicbook/{{Supergirl}}, who was adopted by Brainiac. The three characters would have been involved in a LoveTriangle, with a jealous Brainiac turning Superman evil and Supergirl agreeing to marry him if he returned Superman to normal. Superman would have made a deal with Mxyzptlk to transport him and Brainiac to another dimension in order to settle the matter without superpowers, which they would have done by jousting in medieval armor.
** Creator/AlanAlda and Frank Langella were both considered for the role of Ross Webster. [[Film/SupermanReturns At least Frank got a role later.]]
** Creator/JenniferJasonLeigh was originally set to star as Lana Lang, but turned down the role because she was too young.
** Gus Gorman was meant to be the human guise of Brainiac.
* Creator/ChristopherReeve threatened not to return for this film in protest of the treatment of Creator/RichardDonner and also because he hated the script. With the film already in preproduction, the producers scrambled to find an actor to play Superman. Creator/JohnTravolta was approached but declined. Creator/JeffBridges and Creator/KurtRussell were also considered but were also not interested. Finally with filming days away from beginning, the Salkinds settled on Tony Danza. Richard Lester was mortified with the casting of Danza and pleaded for Reeve to return. Reeve eventually agreed under the condition that he could make numerous changes to the script. The producers agreed and Reeve reprised his role.
* WorkingTitle: ''Superman vs. Superman''. The producers of ''Film/KramerVsKramer'' threatened a lawsuit, refusing to believe the Salkinds' explanation that it was intended as a play on various "Superman vs..." comic stories. Eventually Pierre Spengler suggested that ''Superman III'' would be a more sensible title anyway, and the issue was dropped.
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