David heads into the belly of the beast, the beer spattered streets of Glasgow's night life. Here David will uncover the victims of an unknown serial killer from the 1970s. During a 6 month window the "Weekend Killer" plagued the pubs and dancehalls of Glasgow looking for his next victim and David is going to see how all these poor women connect.In the studio, David speaks with former Deputy Chief Constable Tom Wood, the officer in overall command of ‘Operation Trinity' which was formed in 2004 to examine the life and crimes of Angus Sinclair. Tom explains in great detail how the, almost identical, circumstances of Anna Kenny, Hilda McAuley and Agnes Cooney's murders convinced him that the perpetrator could only be Angus Sinclair after he was identified as responsible for the deaths of Helen Scott and Christine Eadie (The World's End Murders - 1977 – Edinburgh).David is joined in the studio by our resident Forensic Scientist Helen Meadows. This week Helen will dissect the three victims of the weekend killer, Anna Kenny, Hilda McAuely and Agnes Cooney. Helen will examine the MO of all three women and see if they are all linked and if they could in fact have been killed by the same man. The man being Angus Sinclair. Helen will also examine Sinclair's most famous victims Christine Eadie and Helen Scott, again looking for similarities with the Weekend killer.David's final guest is renowned Forensic Psychologist Vicky Thakordas-Desai. She has spent her career trying to understand the mind of a killer. She is joining us in studio to discuss why some murderers refuse, even after being caught, to own up to what they did. Why do they keep these secrets, is it to cause more pain to their victims' family? Or is this their last ounce of control in prison?