Ability over Appearance: Fiona Volpe was originally an Irish girl named Fiona Kelly. When Luciana Paluzzi was chosen for that role over Domino, she was made Italian.
Acting for Two: Paul Stassino plays both Francois Derval and his impostor Angelo Palazzi since Palazzi's real face and voice are never heard or seen.
Awesome, Dear Boy: Luciana Paluzzi originally auditioned for the role of Domino. She remarked later that getting to play the Femme Fatale Fiona Volpe turned out to be a lot more fun than being a Bond Girl.
Cast the Expert: The B-17 that picks up Bond and Domino at the end of the film was owned by a CIA front company and its Skyhook system was actually used in real life on at least one espionage mission - Project COLDFEET.
Luciana Paluzzi auditioned for Domino, but was cast as Fiona instead. She later remarked it was a lot more fun playing a badass female operator than The Heart.
One of Ian Fleming's previous choices to play Bond, Edward Underdown, has a small role as an RAF officer.
007 Averts SPECTRE/007 Averted The Spectre (China)
Thunderball Fighting (Japan)
Operation Thunder (Belgium, France, Spain and Latin America)
Operation Thunderball (Italy, Japan and Poland)
Creator Backlash: Screenwriter Richard Maibaum admitted that he was unhappy with the casting of Adolfo Celi as the main villain.
Creator Killer: An unusual instance where a work did this because it was successful rather than a critical and/or commercial failure. Kevin McClory treated his rights to the story as his own personal cash cow and spent the rest of his career trying to get Thunderball-derived stories off the ground — the only fruit of which was Never Say Never Again, which did decently at the box-office but didn't set the world alight — to the exclusion of all else. It didn't help that his vocal support for a United Ireland got him blackballed in the UK film industry, while American studios quickly became wary of dealing with him due to his constant litigation with EON Productions and other parties who he felt were infringing on his rights.
Enforced Method Acting: Sean Connery and the sharks in Largo's pool. The clear plastic panels that shielded Connery from the sharks could only extended about three feet in height and sharks could swim over them. Some sharks did and Connery was genuinely terrified. Guess which takes the director used in the film?
A justified example, with the decision to change Largo's death from a gruesome harpoon through the neck, to a relatively more tame but more dramatic harpoon through the back.
The producers deciding at the last moment to require the theme song to have the word "Thunderball" in it, necessitating some quick rerecording and quick rescoring to fit the new song in.
Fake Nationality: George Pravda, who played a Polish scientist, was Czechoslovakian.
I have never been able to play a game of cards and they were compelled to tell me all from the beginning to end. The only reason why I had that cool and detached face was that I didn't care at all. I was completely out of it. As I said "Banco!", everyone said, "Look how well that one says "Banco!"
Keep Circulating the Tapes: It took almost thirty years for the expanded soundtrack to be released. This was because John Barry was still scoring the second half of this movie when the music for the recording of the soundtrack was required. Practically no music from the second half of the movie appeared in the original score's release. While the eighty minute CD is largely complete, it is still missing about twenty-five minutes of extra music.
Robert Rietti's voice replaced Adolfo Celi'snote Which caused problems when Celi was cast as Rodrigo Borgia in the 1981 BBC mini-series The Borgias; the casting director had no idea Celi had been dubbed in the film, and his almost impenetrable Italian accent rendered most of his lines a garbled mess., while Nikki Van Der Zyl overdubbed Claudine Auger's French accent in the role of Domino. Amazingly enough, Italian-born Luciana Paluzzi, who played villainess Fiona Volpe and had a long list of credits in English-language films and TV, was NOT dubbed.
Q introduces Bond to his new tricked-out briefcase, accompanied by the line "Now pay attention, 007". This line would later become one of many famous motifs in the series, but Desmond Llewelyn does not move his mouth.
Missing Trailer Scene: The trailer has Bond say to Fiona, "The things I do for England". He doesn't say it here, but he does in the next one. There's also a scene of Largo scratching his eyepatch that isn't in the film.
No Stunt Double: An excellent swimmer, Claudine Auger did all her own underwater scenes including a love scene with Sean Connery on the sea bed during which she lost her bikini top.
Orphaned Reference: Largo asking Bond if he'd like to look over the Disco Volante was supposed to lead into a scene where Largo gives Bond a tour of the boat. Bond would use his geiger counter watch to look for the bombs, only to come up with nothing.
Felix Leiter is recast yet again, this time with Rik Van Nutter, apparently doing his best impression of Jack Lord (who played Leiter in Dr. No), with Leiter once again being depicted as a young man after the previous film had him grey-haired and middle-aged.
Possibly happened with the voice of Blofeld as well, as various sources claim that Joseph Wiseman (the titular Dr. No) took over the role from previous actor Eric Pohlmann in this film, while yet others say that it was still Pohlmann.
Reality Subtext: When strapping on the jetpack, Bond takes a moment to put on a helmet. This was because Bill Suiter, who did the actual flying, absolutely refused to operate the jetpack without a helmet and the crew had no choice but to acquiesce because no one else could perform the stunt and survive.
Recursive Adaptation: The film was based upon Fleming's novel, Thunderball, which was in turn adapted from an unproduced screenplay from the 1950s.
The Red Stapler: Some companies were interested in the miniature breathing apparatus used by Bond in one scene, not knowing it was a prop.
Release Date Change: The movie was originally supposed to have had its premiere at the Odeon, Leicester Square, London in September 1965. It was delayed until December, because it could not be completed in time.
Spared by the Cut: Pinder was originally supposed to accompany Bond on his raid on Palmyra and die in shoot-out.
Regular stuntman Bob Simmons played Col. Jacques Bouvoir. He also doubled for Guy Doleman in Count Lippe's death scene and was lucky to escape with his life.
Bond's jetpack was actually flown by engineer Bill Suiter. He was one of only two people in the world qualified to fly it.
Mid-Development Genre Shift: Ian Fleming originally conceived the story with Kevin McClory and Jack Whittingham as either a film or a television pilot. When that fell through, he adapted the script into a novel.
Reality Subtext: Bond's medical record, as read out to him by M, is a slightly modified version of Fleming's own.
Working Title: SPECTRE, James Bond of the Secret Service and Longitude 78 West.
Write What You Know: The visit to the health clinic was inspired by Ian Fleming's own 1955 trip to the Enton Hall health farm. He was ordered by his doctor to go to one and found the experience so laborious that he began to plot out his next book to give himself some relief from it all.
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