Thunderbirds Are Go is a 1966 British science-fiction puppet film based on Thunderbirds, a Supermarionation television series created by Gerry and Sylvia Anderson and produced by their company Century 21 Productions. Written by the Andersons and directed by David Lane, Thunderbirds Are Go concerns spacecraft Zero-X and its human mission to Mars. When Zero-X suffers a malfunction during re-entry, it is up to life-saving organisation International Rescue, supported by its technologically-advanced Thunderbird machines, to activate the trapped crew's escape pod before the spacecraft hits the ground.

Thunderbirds is a British science fiction television series created by Gerry and Sylvia Anderson, filmed by their production company AP Films (APF) and distributed by ITC Entertainment. It was made between 1964 and 1966 using a form of electronic marionette puppetry combined with scale model special effects sequences. Two series, totalling thirty-two 50-minute episodes, were filmed; production ended with the completion of the sixth episode of the second series after Lew Grade, the Andersons' financial backer, failed in his bid to sell the programme to American network television.