1. Arnold Schwarzenegger auditioned for the role of the Hulk but was rejected by producer/developer Kenneth Johnson due to "his inadequate height".
2. Actor Richard Kiel (who is most famous for playing Jaws in the James Bond films The Spy Who Loved Me and Moonraker) was initially hired for the role of the Hulk, but during filming of the pilot episode the producers felt he didn't look menacing enough so sacked him, replacing him with bodybuilder Lou Ferrigno. Although most scenes were re-shot with Ferrigno, a small moment of Kiel Hulk-out still appears in the pilot episode - that's Kiel below...
3. For the role of Dr. David Banner, Kenneth Johnson cast Bill Bixby - his first choice for the role. In the original comic books, and the more recent Marvel Cinematic movies the characters name is Dr. Bruce Banner. According to both Stan Lee and Lou Ferrigno, the name was changed because network CBS thought the name Bruce sounded "too gay-ish", a rationale that Ferrigno thought was "the most absurd, ridiculous thing [he had] ever heard". However, on the DVD commentary of the pilot, Johnson says that the name change was a way to honor his son David.
(Bruce did appear as the TV characters middle name. It is visible on Banner's tombstone at the end of the pilot movie, and that footage is shown at the beginning of every episode of the series.)
4. The opening narration was provided by actor Ted Cassidy (best known for playing Lurch in”The Addams Family”), who also provided the Hulk's voice-overs (mainly growls and roars) during the first two seasons.
Sadly, Cassidy died during production of season two in January 1979. The Hulk's vocalisations for the remainder of the series were provided by actor Charles Napier, who also made two guest-starring appearances in the series.
5. In an interview with Kenneth Johnson on the Season 2 DVD, he explains that he had wanted the Hulk to be colored red rather than green. His reasons given for this were because red, not green, is perceived as the color of rage, and also because red is a "human color" whereas green is not. However, Stan Lee rejected his plea and stood firm, stating that the Hulk's color was not something that could be changed, because of its iconic image.
6. Because David Banner never has any recollection of his actions as the Hulk, Bill Bixby did not watch Lou Ferrigno perform on set, and Ferrigno was never present for Bixby's scenes. This process remained for all but one episode of the original five season run, it was only broken for the season four episode 'Bring Me the Head of the Hulk' and the final two made-for-TV-movies in 1989 & 1990 because all were directed by Bixby.
7. Initially, Bixby was very careful never to be photographed with Lou Ferrigno in his Hulk makeup because he felt for photos to get out of the two of them together would destroy the illusion to children and fans of the show that they were not the same person.
During the first season of the show the tabloids of that era were always trying to get a picture of David Banner and the Hulk creature together but were unable to do so. Their first shared photo appeared on the cover of US Weekly, dated July 11th 1978, two weeks after the last episode of season one had been broadcast.
8. Although the Hulk is always barefoot in outdoor scenes Lou Ferrigno often wore Hulk-green slippers to protect his feet. These are most noticeable in the season one episode 'Terror in Times Square', as the Hulk storms through the streets of New York. Ferrigno once joked that even the mighty Hulk wouldn't want to go barefoot in Times Square in the 1970s.
9. To avoid sweating, which caused his green makeup to come off, Lou Ferrigno spent much of his time in between takes in a customised refrigerated motor home.
10. Today, every Marvel Cinematic release features a cameo by Stan Lee, but this is nothing new. Lee had a cameo in the 1989 post-series TV movie, Trial Of The Incredible Hulk, where he appeared as one of the jury members. Co-Hulk creator, artist Jack Kirby also had a cameo in the series. His came some years earlier in the season two episode 'No Escape'.
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