The pursuit of justice for George Murdoch intensifies. A significant breakthrough has provided police with a DNA profile believed to come from George's killer, but it hasn't matched to any known offender. Undeterred, detectives track down people across the UK with similar DNA, who could be blood relatives. Finding a family member could lead them directly to the door of the man who murdered George.

Affectionately known as "Dod," George was a beloved family man and the brutality of his murder in 1983 – attacked with a cheesewire then strangled to death – left an enduring scar on his loved ones and the wider Aberdeen community. This film delves into the profound emotional toll the unsolved crime took and what the public can now do to help find George's killer.

To refine their search, detectives enlist the expertise of a Behavioral Investigative Adviser from the National Crime Agency. By meticulously analysing the crime scene and witness statements, he develops a psychological and criminal profile of the killer, aiding their manhunt.

David, a childhood neighbour of George and his wife Jessie, recalls the night of the murder and its devastating long-term impact on Jessie. The murder haunted the widow for the rest of her life: she was in constant fear that the killer, who had taken George's wallet with their address inside, would come for her next.

The film culminates in Senior Investigating Officer James Callander and journalist Kirsty Wark exploring the crucial clues uncovered throughout the investigation, and reveals how the public can assist detectives in finally cracking this long-unsolved crime.