Bang. Unwin was the creator of "Unwinese", a form of gibberish that was outwardly unintelligible but retained some aspects of meaning. Anderson remembered Unwin's radio and TV performances using the language and thought that it would suit the character of a secret agent, also reasoning that it would have comic value if shown to confuse the enemy. In his biography, he explained: "As far as I was concerned, Stanley came first and then the idea had to accommodate him. It wasn't that the story called for someone who could speak gobbledygook, it was a question of how we could fit him into the storyline." Due to the esoteric nature of Unwinese, the writers briefed Unwin on the storylines and left space in their scripts for him to draft all the gibberish dialogue himself. Shane Rimmer, who wrote the episode "Hole in One", recalled that "A lot of [the dialogue] you had to leave to [Unwin]. You gave him a line of patter that's going to work with what he does. Because he was such a bizarre character, you felt you could really go all the way with him: you could practically do anything." The premise of The Secret Service was inspired partly by the Joe 90 episode "The Unorthodox Shepherd", which features an elderly and seemingly half-deaf vicar who is covering up a money forging operation on the grounds of his church. Anderson's biographers Simon Archer and Marcus Hearn believe that Joe 90 also had a broader influence on its successor, writing that The Secret Service "continues the espionage theme of Joe 90 in a range of adventures that depict a Britain under siege from despicable foreign agents intent on stealing its secrets." Puppets After Joe 90, Anderson had intended to abandon Supermarionation puppets altogether in favour of using live actors. For reasons of economy, he eventually opted for a hybrid format that blended scale puppet sequences with footage of live actors filmed in full-sized surroundings. On the style of the puppets – which, after Thunderbirds, had been re-designed with realistic body proportions – Anderson said that Century 21's ever-improving sculpting techniques had produced "imitations of human beings" that made the company's puppet series "like live-action shows but with unconvincing actors". To avoid the long-running problem of making the puppets walk convincingly, the series often used footage of live actors in long shot for scenes that required characters to move.