All of the country's early warning systems bar one go off, mistakenly suggesting a nuclear attack. When land is about to be sold, adjacent to the one that was not sounded, interested buyers are invited to a fancy dress party on board a train. Steed, dressed as a gambler, and Mrs. Gale, a monk - and later a highwaywoman - join the party, where they meet the likes of Robin Hood and Napoleon Bonaparte and have to decide which one is a killer and why?
—don @ minifie-1