Trivia: Jeff Tracy's five sons were named after Mercury astronauts - Scott Carpenter, Virgil Grissom, Alan Shephard, Gordon Cooper and John Glenn.
Trivia: Although he is the main villain, the Hood appears in only six episodes throughout the entire series.
Trivia: The Hood's name was never used in the TV series. It was revealed in spin-off media and promotional materials.
Trivia: Fenella Fielding was Gerry Anderson's first choice for the voice of Lady Penelope.
Trivia: Each episode's opening credit scene would feature some highlights of the episode. Gerry Anderson would later use this gimmick in "Space: 1999" and "Space Precinct".
Trivia: In the opening credits, you see a picture of Thunderbird 3 in the background, but Alan Tracy is not flying the craft. He in is fact flying Thunderbird 2 with the steering wheel upside down.
Trivia: International Rescue's headquarters was never actually referred to as "Tracy Island" throughout the whole series.
Trivia: Jeff, Scott and Virgil are the only characters to appear in all 32 episodes of the show.
Trivia: Gerry Anderson modeled members of the Tracy family on Hollywood actors: Jeff was modeled after Lorne Greene, Alan after Robert Reed, Scott after Sean Connery and John after Charlton Heston.
Trivia: At Tracy Island there are portraits on the wall of Jeff Tracy's five sons: John, Scott, Virgil, Alan and Gordon. Gordon's portrait never bleeped once during all thirty-two episodes of the show.
