Air date: 2014-08-20

Runtime: 45 min

In the first of a two-part story, DI Martha Bellamy's neighbour, barrister Jonathan Moxton, is discovered at his home with serious head injuries, his wrists bound with a belt and a pair of knickers stuffed in his mouth. DS Jack Weston guesses he was involved in a sex game that went badly wrong and suspicion falls on Saul Hammond, the man who found him.

Air date: 2014-08-21

Runtime: 45 min

The body of a student, Michael Collins is found on Crowford common. The killer is suspected to be the person who attacked Moxton.

Air date: 2014-08-27

Runtime: 45 min

Jack leads an investigation into the dark world of child sex offenders. He becomes too emotionally involved within the case after a brutal attack is made on an amateur paedophile hunter Scott Freeman.

Air date: 2014-08-28

Runtime: 45 min

The suspected leader of the paedophile ring is murdered and the hunt is on to find the killer.