On 18 May 1991, Lesley Howell (31) and Trevor Buchanan (32) were murdered in County Londonderry, Northern Ireland, in a staged double killing carried out by Howell's husband, Colin Howell, who sought to disguise their deaths as a suicide pact. At the time, Colin Howell had resumed an extra-marital affair with Buchanan’s wife, Hazel; in his later confession, he stated that the affair formed part of the circumstances leading to the killings. The case remained officially closed for almost two decades until Colin Howell confessed in 2009, leading to his conviction and that of Hazel. The killings, subsequent investigation and later trials attracted significant public attention and were later dramatised in the ITV series The Secret, broadcast in April and May 2016. The confession tape was broadcast in a BBC documentary in January 2026.