Colonel March of Scotland Yard is a British television series consisting of a single series of 26 episodes first broadcast in the United States from December 1954 to Spring of 1955. The series premiered on British television on 24 September 1955 on the newly opened ITV London station for the weekends Associated Television. It is based on author John Dickson Carr's (aka Carter Dickson) fictional detective Colonel March from his book The Department of Queer Complaints (1940). Carr was a mystery author who specialised in locked-room whodunnits and other 'impossible' crimes: murder mysteries that seemed to defy possibility. The stories of the television series followed in the same vein with March solving cases that baffle Scotland Yard and the British police. The department itself is sometimes referred to as "D3". Boris Karloff starred as Colonel March.