Sylvia Anderson first episode of a series then sharing the work according to their strengths. Gerry tended to specialise in special effects and hardware, and Sylvia in character, voices, costume, dialogue, and plotlines. In this way, Anderson contributed plot development and voice work for a series of half-hour shows including "Supercar", "Stingray" and "Fireball XL5". However, she felt the half-hour format was insufficient to fully develop characters and stories, and she persuaded the team's TV producer Lew Grade to extend their shows to a full hour. In the early 1960s, the Andersons co-created the series "Thunderbirds", and Sylvia created the characters. She
Sylvia Anderson in 1968, Turner commented: "we wanted a glamorous blonde and [Anderson] was the obvious choice." In 1966 and 1968, Anderson produced two feature-length films based on the "Thunderbirds" story, "Thunderbirds Are Go" and "Thunderbird 6". She was co-creator with Gerry Anderson for the series "UFO" (1969-1970) on which she co-produced, was responsible for fashions on the show, and did the majority of the casting. The Andersons' creative partnership ended when their marriage broke down during the production of the of "" in 1975. Gerry announced his intention to separate on the evening of the wrap party, following which Sylvia ceased