A new ITV drama series called The Pembrokeshire Murders will take a deep delve into the pursuit of a cold-blooded serial killer.
It took 25 years of police investigation to bring John Cooper, also known as the Bullseye Murderer, to justice.
The Welshman from Pembrokeshire seemed a friendly character to most people, but on the inside he was capable of extreme violence.
Cooper committed heinous crimes between 1985 and 1989, which sent shockwaves through Wales and further afield.
He was a prolific burglar – Cooper also committed two double murders.
So who were his victims? Here we take a closer look at who his victims were.
Richard and Helen Thomas
Brother and sister Richard, 58, and Helen Tomas, 56, were killed on December 22 1985.
Cooper robbed their three-story farmhouse at Scoveston Park, Milford Haven.
At the same time he attacked the pair, threatened them with a shotgun before tying them up.
He robbed them and shot them at close range, before setting fire to the house in order to destroy evidence.
At the hearing after Cooper was caught, the Thomas family said their memories “will remain with us all forever but we hope that we will now be able to remember the happier times more than the very sad ones”.
Peter and Gwenda Dixon
Couple Peter, 51, and Gwenda Dixon, 52, were killed on June 29, 1989.
Peter was a marketing manager and his wife was a secretary for her local social services department in Witney, Oxfordshire.
They were spending the holidays at the Howelston Camping and Caravan Park, near Little Haven.
On their last day they decided to dry out their tent while they went for a walk on the coastline.
They were confronted by Cooper, dressed in a black balaclava, who was pointing a shotgun at them.
They were tied up and robbed, with Peter being forced to hand over his bank card and pin number.
Both victims were shot at close range.
At the hearing, the Dixon’s children Tim and Julie Ann paid tribute to their parents who them called “loving, gentle and charismatic”.
Cooper was also convicted of separate charges of rape, sexual assault and attempted robbery.