The case of `jigsaw killer' Stephen Marshall, who murdered businessman Jeffrey Howe in March 2009 and scattered his body parts in locations around Hertfordshire and Leicestershire. Featuring interviews with police officers involved, the programme reveals how the grisly case was solved, with Marshall sentenced to life imprisonment in February 2010 and his girlfriend Sarah Bush jailed for three years and nine months for perverting the course of justice.

• Mark Austin