For the first time, Scotland Yard opens its secret files to bring us the authentic true stories of some of its most famous cases. The title comes from the emergency telephone number in use at the time, and the series was introduced by Chief Superintendent Davidson, curator of the Crime Museum – more commonly known as the “Black Museum” - at Scotland Yard, London, England

A case of arsenic poisoning is examined, along with the prime suspect - and the not-so-likely suspects.