The murder of four members of the Ding family by Anxiang Du in Northamptonshire in 2011, focusing on the key error that he made which led to his arrest.
An in-depth look at how police brought Tony McCluskie to justice after he murdered and dismembered his sister, EastEnders actress Gemma McCluskie, in 2012.
A look at the key errors made by murderers that led to their arrest, focusing this time on Paul Hutchinson, who abducted, raped and strangled Colette Aram in 1983.