Whodunnit?Season 51977 · 5 episodesEpisodes1The Rajah's RubyIt's 1925, and a daring thief makes off with a precious gemstone.2Village FateRehearsals for a murder mystery play turn sinister when one of the actors is poisoned for real.3No Happy ReturnsSeventieth birthday celebrations for a bad-tempered Chairman of the Board end with a bang!4The Q43 ExperimentA top British scientist is gunned down as he works in his laboratory.5Last Tango in TootingIt's the finals of the Banworth Chemical Works dance competition and there's murder on the dancefloor.Season 1Season 2Season 3Season 4Season 6