Joe 90 is a late-1960s British science-fiction television series documenting the exploits of a nine-year-old boy, Joe McClaine, who embarks on a double life as a schoolboy turned spy when his scientist father invents a pioneering machine capable of duplicating and transferring expert knowledge and experience to another human brain. Equipped with the skills of the foremost academic and military minds, Joe enlists in the World Intelligence Network (WIN), becoming its "Most Special Agent", pursuing the ideal of world peace and saving human life. Created by Gerry and Sylvia Anderson and filmed by Century 21 Productions, the 30-episode series followed the earlier Thunderbirds and Captain Scarlet and the Mysterons.
First screened in the UK from September 1968 to April 1969 on the ATV network, Joe 90 was the sixth and final Anderson production to have been made exclusively using the form of marionette puppetry dubbed "Supermarionation". The final puppet series, The Secret Service used this process only in combination with extensive live-action filming. As in the case of its predecessor, Captain Scarlet, the puppets of Joe 90 are of a more naturally proportioned design as opposed to the more caricatured appearance of the characters from Thunderbirds.
Although not as successful as Century 21's previous puppet efforts, since its inception, Joe 90 has been praised, besides other aspects, for the characterisation of its smaller Supermarionation cast and the accomplishment of its model sets and special effects. Critics read into Joe 90's spy-fi theme and the choice of a child character as the protagonist, suggesting either a "kids play Bond" connection or an enshrinement of children and the powers of their imagination. Points for criticism range from the violence depicted in a number of episodes to the absence of female characters, which is viewed either as the inevitable result of Joe 90's development as a "boy's own adventure" or bordering on sexism.
As had been the case for its precursors, Century 21 based merchandising campaigns on Joe 90, which included toy cars and comic strips dedicated to the continuing adventures of Joe McClaine. Syndicated on its arrival in the United States in 1969, re-broadcast in the UK during the 1990s and released on DVD in most regions in the 2000s, the concept of a live-action motion picture adaptation of Joe 90 has been considered more than once since the 1960s, although without further development. A comparable format exists in the similarly titled Ben 10; while Joe 90 has access to the knowledge and experience of scientists and military personnel while wearing his glasses, Ben 10 acquires alien powers while wearing a watch.