After Margot Kidder expressed her disgust about the firing of Richard Donner to the producers, her role was cut to 12 lines, and less than 5 minutes of screen time, but Ilya Salkind says Margot's claim is untrue. On the 2006 Superman III DVD commentary Ilya states that there was little need for Lois Lane in this movie since her and Superman's relationship ended at the end of Superman II.
Richard Pryor was said to have been cast in the movie as a result of comments that he made during an appearance on The Tonight Show Starring Johnny Carson (1962). During an interview segment, Pryor told host Johnny Carson that he wanted to be in a "Superman" movie. He later claimed that he was only joking about doing such a movie, but the film's producers thought that he was serious about it.
According to Ilya Salkind, an earlier version of the script included the comic book villains Brainiac and Mr. Mxyzptlk teaming up, and Superman meeting his cousin, Supergirl, which would lead to the potential Supergirl spin-off.
According to the producers' commentary on the Superman III: Deluxe Edition DVD, this film was actually not a flop. While critics and fans generally expressed disappointment with the film, and its $60 million gross fell short of the previous two movies' $100 million+ gross, Superman III still made an impressive profit, despite stiff competition from Star Wars: Episode VI - Return of the Jedi (1983) (which opened 3 weeks earlier) and Octopussy (1983) (which opened 10 days earlier).
The tar-laced kryptonite that Superman is exposed to has the effects of both red and black kryptonite. Red, particulary in the show Smallville, releases all Clark's inhibitions. The persona-splitting scene was inspiration for the first appearance of black kryptonite in Smallville. It could seperate Clark from his darker side. The battle in the junkyard is considered the most iconic scene of the movie.
The video game Ross Webster plays that was created for the film, was made by the Atari Corporation. However, The Atari Corporation had made a "Superman III" video game, based on the film for the Atari 5200, but was never released.
The original title was "Superman vs. Superman". The producers of Kramer vs. Kramer (1979) 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.
The song "Earth Angel" by The Penguins is played during the Smallville High School reunion dance attended by Clark Kent (Christopher Reeve) and Lana Lang (Annette O'Toole). It was also played during the Enchantment Under the Sea dance at Hill Valley School on November 12, 1955 in Back to the Future (1985). Marc McClure (Jimmy Olsen) also appeared in that film, in which he played Marty McFly's elder brother Dave McFly.
Superman/Clark Kent's hair in this movie is obviously brown and not black as seen in the first two films. That's because Christopher Reeve is wearing a wig throughout the entire movie, unlike the first two films where he dyed his natural hair black.
According to the writers, the original choice to play Ross Webster was Alan Alda. They wanted an actor who could be ruthless without losing any charm. Executive producer Ilya Salkind said in the DVD commentary that his choice was Frank Langella. Langella later starred as Perry White in Superman Returns (2006).
Frank Oz played a brain surgeon in a deleted scene from the montage of the supercomputer causing a nationwide power outage. It's included in the extended TV version of the film. He also worked on puppet sequences, which were also deleted, and not included in any version. The film's director of photography, Robert Paynter, previously shot An American Werewolf in London (1981), in which Oz appeared, and would go on to shoot The Muppets Take Manhattan (1984) (Oz's directorial debut) and Little Shop of Horrors (1986).
According to the Vulcan weather satellite, the chemical composition of Kryptonite (shown on Gus Gorman's computer) is: 15.08% Plutonium, 18.06% Tantalum, 27.71% Xenon, 24.02% Promethium, 10.62% Dialium, 3.94% Mercury, and 0.57% Unknown (Gorman replaced this with Tar).
During the Smallville High School Reunion Dance, you can hear "Roll Over Beethoven", a Chuck Berry song covered by The Beatles (with George Harrison singing lead). Director Richard Lester also directed the Beatles' first two films "A Hard Day's Night" and "Help!"
Enid Saunders character, Minnie Bannister (in one of the Smallville sequences), is a very obscure in-joke by Richard Lester. He had a long association with the cast members of the BBC radio show "The Goon Show." Minnie Bannister, voiced by Spike Milligan, was a recurring character.
The only Superman film, not to feature the fortress of solitude, Jor El or Lara and even any mention of the events of the first two films, except for Lois's interview with Superman and his weakness towards kryptonite.
Noel Neill who played Lois Lane in both the Superman serials and the TV show can be viewed in a cameo as an old woman on the dais in Smallville just after Superman (Reeves) receives the key to the city.
The trivia items below may give away important plot points.
Richard Pryor's character steals money from his company by collecting fractions of a cent from other accounts and collecting them in his personal account. In computer crime terminology, it's called the "salami technique."
Filmed in Calgary, Alberta, home of Canada's first Kentucky Fried Chicken franchise. It includes multiple KFC references: the Metropolis computer school payroll is handed out by a man in a Sanders-style goatee, Gus walks past a Smallville display with Kentucky Colonel outfits, Gus drags the intoxicated Brad past a closet whose open door shows a bag hanging full of KFC items, and Gus uses a "chicken in the bucket" recipe to explain to Ross why Kryptonite doesn't kill Superman.
Both Annette O'Toole (Lana Lang) and Margot Kidder (Lois Lane), meet for the first time in this movie. Both actresses, would reunite during the 4th season premier of Smallville in 2004. At that point, O'Toole was playing Martha Kent and Margot Kidder as Bridgette Crosby. The character was a supposed love interest for Dr. Virgil Swan (Christopher Reeve).
The films continuity is out of place. In Superman: The Movie, Lex Luthor mentions that Krypton exploded in 1948. Which means that the scene featuring young Clark, was in 1966, the year that he had turned 18; as mentioned by Jor El. After Jor El's tutelage, he tells Clark that 12 of his years have passed (meaning that it was 1978). However in Superman III, Clark 's school reunion says class of '65. In this case, the film takes place in 1980, instead of 1983, so that the proper school reunion, would be 15 years. Gus Gorman pulls his sports car into Webscoe and the song "No see, no cry!" is playing by Chaka Khan. The song was released in 1983.