"Big Ben Strikes Again" is the third episode of Captain Scarlet and the Mysterons, a British 1960s Supermarionation television series co-created by Gerry and Sylvia Anderson. Written by Tony Barwick and directed by Brian Burgess, it was first broadcast on 13 October 1967 on ATV Midlands. In this episode, the Mysterons attempt to destroy London by hi-jacking a transporter carrying an atomic device.