Captain Scarlet vs. the Mysterons is a 1981 television film based on the 1960s British puppet TV series Captain Scarlet and the Mysterons created by Gerry and Sylvia Anderson. Produced by the New York office of the series' distributor, ITC Entertainment, the film is a compilation of the Captain Scarlet episodes "The Mysterons", "Winged Assassin", "Seek and Destroy" and "Attack on Cloudbase". It follows an earlier Captain Scarlet compilation, Revenge of the Mysterons from Mars.

"The Mysterons" is the first episode of Captain Scarlet and the Mysterons, a British Supermarionation television series created by Gerry and Sylvia Anderson and filmed by their production company Century 21 Productions. Written by the Andersons and directed by Desmond Saunders, it was first officially broadcast on 29 September 1967 on ATV Midlands, although it had received an unscheduled test screening in the London area five months earlier.