Nicola Walker voices moving first-look clip for new crime documentary Forensics: Murder Case

In an exclusive clip shared with RadioTimes.com, a friend of George's, David Wright, reflects on his friendship with George, with whom he first began fishing as a youngster.

"I remember always being out on his boat, we always used to catch fish," David says. "Lots of happy memories and good times with him."

Viewers can watch on as Walker narrates the clip, offering a better idea of George and David's friendship as David goes on to detail the night he discovered George had died.

"The impact of his murder on George 'Dod' Murdoch's wife Jessie was unthinkable," Walker can be heard saying, with David adding: "Part of her died that night as well, 100 per cent. She always had this fear that whoever had killed Dod... that he was going to come and get her."

The police investigation into George's death has never been closed, but the murderer's identity has remained a mystery since that fateful night in 1983.

"Somebody out there knows they did it and they've protected them for 40 years. How you can protect somebody that's taken a life is beyond me," the clip concludes.

You can watch the full video above.

Over 40 years later, a DNA profile from preserved crime scene evidence has come to light that police believe could belong to George's killer.

The docuseries features exclusive access to those closest to George and those who worked on the case, offering "a rare glimpse into the inner workings of a cold case investigation, revealing the painstaking efforts to piece together fragments of the past to help solve the crime in the present".

The synopsis continues: "Detectives from the '80s onwards have been haunted by this case; George Murdoch’s killer is the one that got away.

"The police of the past, however, were hampered by the lack of CCTV and mobile phone evidence – resources indispensable to a modern-day inquiry.

"Despite conducting 10,000 house-to-house inquiries and recording 7,000 statements, the killer has remained beyond their grasp.

"But now the net is closing, and the public have a vital role to play. The killer’s DNA hasn’t matched to a profile on the national database, but detectives have the next best thing – a list of possible blood relatives that could lead them to the door of a murderer."

Forensics: Murder Case is coming to 5 on Monday 21st July.

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