"Crater 101" is the 21st 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 Tony Barwick and directed by Ken Turner, it was first broadcast on 26 January 1968 on ATV Midlands. The episode is one of four that were later re‑edited and combined to create Revenge of the Mysterons from Mars (1981), a Captain Scarlet compilation film produced by the New York office of distributor ITC Entertainment.