Is ITV’s Gone based on a true story?

From the outside looking in, the Polly family in ITV's Gone appear to be the picture of harmony.

Michael (David Morrissey) is the headmaster of a prestigious private school, while his wife Sarah and their daughter Alana (Emma Appleton) are also teachers at the same famed institution.

But one afternoon, Michael and Alana return home to discover that Sarah is missing.

After waiting in the hope that she will walk through their front door, they eventually contact the police and a missing persons investigation is launched.

But DS Annie Cassidy (Eve Myles), who is assigned the role of family liaison officer, is almost immediately suspicious of Michael. Not only does he appear entirely unmoved by the situation at hand, he appears more concerned with running the school and coaching the rugby team than engaging with the police, or comforting his daughter.

But is Michael simply a product of his environment? Or is there a far more sinister reason for his chilling behaviour?

Running alongside the central investigation, Annie remains haunted by a historic case she was unable to solve: the disappearance of a young woman called Tina Bradley.

Over the past eight years, the detective has grown close to the victim's mother, Carol, but as time continues to pass with no further developments, she "appears to be losing faith in her".

"Will Annie ever find justice for Carol's daughter?" asks the official synopsis.

Read more:

• Torchwood legend Eve Myles reveals why dark new drama "took its toll a bit"

While the central investigation in Gone is a work of fiction, the cold case storyline is inspired by a distressing real-life case, which you can read about below.

Is Gone based on a true story?

The Sarah Polly case in Gone is entirely fictional, but the drama is partly inspired by the work of former Detective Superintendent Julie Mackay of Gloucestershire Police, who solved the cold case murder of 17-year-old Melanie Road, more than three decades on.

"They've taken my cold-case journey — which was up and down, two steps forward, three steps back, endless dead ends – and told a different story," McKay told Radio Times magazine. "I'm very happy about it – Melanie's family don’t want to be in the public eye."

Myles told Radio Times that Melanie's story "is touched upon, the backdrop to the story is very much Julie's story. But it doesn’t domineer this series, and our story veers somewhere completely different".

The teenager was on her way home in June 1984 after a night out with friends at a Bath nightclub when she was attacked.

Melanie was sexually assaulted and stabbed 26 times before her body was discovered by a milkman and his 10-year-old son at 5.30am in front of some garages, a short distance from her home.

For 32 years, there was no justice for Melanie, while her family and friends lived with the unbearable knowledge that her killer was still out there.

But in 2016, Christopher Hampton – who was 32 at the time of Melanie’s murder – was sentenced to life imprisonment after pleading guilty to her murder. Then 64, he was ordered to serve a minimum of 22 years behind bars.

The married father-of-three had initially denied killing Melanie, but the police had matched DNA from her clothing to a member of his family the year before.

Investigators had held a DNA profile of Melanie's suspected killer since 1995, but there had been no match on the national database – that was until DNA from Hampton's daughter was taken following a criminal damage charge, and added to the system.

Checks on the killer's DNA sample were run again in 2015 and matched with the daughter. Police then asked Hampton for a voluntary DNA swab, which proved to be a match with the DNA collected at the crime scene.

"It's a fascinating story, it's an extraordinary case to follow," Eve Myles told Radio Times.

"Coming to something having an anniversary on Crime Watch after 25 years to highlight that the killer hadn’t been caught for this horrendous crime, for Julie to come in after that 25 year anniversary and six years later catch the killer is an extraordinary thing to do.

"So I'm really pleased that it was spotted, and that George [Kay, who write the series] and [director] Richard [Laxton] have highlighted it. It's a story that should absolutely be celebrated, and Julie should be celebrated."

McKay later wrote a book, To Hunt a Killer, with ITV journalist Robert Murphy, detailing Melanie's case alongside several others.

"A few people approached Rob and me about the rights to our book and we ended up working with George Kay," the former detective, who acted as a consultant on the series with Murphy, told Radio Times magazine.

"He's such an inspirational screenwriter – The Long Shadow [about the hunt for serial killer Peter Sutcliffe] was terrific. George asked me about various aspects of police procedure, but I didn't know what the story was until he sent the final scripts, so I just suggested different scenarios. It was exciting!"

As for similarities between her and Myles's character, while they share a profession, McKay was in a very different place in her life when she was in the thick of the Melanie Road investigation.

"Annie Cassidy is a detective sergeant, as I was when I started on the Melanie Road case. It's the rank that works at the coal face, on the nitty-gritty, following up lines of enquiry," she explained.

"Annie is her own person; she's not me at that stage. I was a single mother with three kids – my life was chaotic. Annie is gutsy and intuitive; she's like a dog with a bone, refusing to let things go, even when it’s against the rules."

Meanwhile, Myles described Julie as an "inspirational woman".

"I was lucky enough to make contact with her and have many calls with her, and meet her. She was very generous with her time and her information," she added.

"She's such an inspirational woman and hopefully we've done the story justice on the show."

Gone begins airing on Sunday 8 March on ITV1 and ITVX.

Add Gone to your watchlist on the Radio Times: What to Watch app – download now for daily TV recommendations, features and more.

Check out more of our Drama coverage or visit our TV Guide and Streaming Guide to find out what's on. For more TV recommendations and reviews, listen to The Radio Times Podcast.