Delia Balmer's story has been highlighted in ITV's new true-crime drama Until I Kill You, with Anna Maxwell Martin depicting the real-life person.
The nurse met a man named John Sweeney during a night out in a pub in the early '90s. Little did she know at that point that he was actually a killer. Their relationship became increasingly volatile and, after Delia ended things with John, he returned to her home with an axe and attacked her. Delia's life was saved when a neighbour intervened.
It wasn't until years later that John Sweeney would be found guilty of murdering two of his former girlfriends (via BBC News).
Related: Anna Maxwell Martin's new true-crime drama is the genre at its best
Until I Kill You is based on Delia Balmer's own memoir of her experience with Sweeney; published in 2017, it's titled Living With a Serial Killer.
It's still available to buy on Amazon, and the official synopsis of the book describes how "at first he was caring but over the course of their relationship he became violent and controlling".
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It describes that "on more than one occasion he held Delia hostage and tortured her", and "after one serious assault, Sweeney was released on bail, and left her in the utmost fear knowing that he would return to finish her off. After a final frenzied attack leaving Delia on the brink of death, Sweeney went on the run."
"Astonishingly, it would take the police six years to capture and convict Sweeney of multiple murders."
The true story of Until I Kill You
At the start of the episodes on ITV, a message reads: "This is a true story. What follows is based on extensive research, interviews and published accounts. Some names have been changed, and some characters and scenes added for the purposes of dramatisation."
According to producer Ken Horn, the show "changed some names out of reverence to the families" (via quotes published by Time Out).
The publication also reported that Horn explained how the character of Delia's friend Leah (played by Amanda Wilkin) was based on a combination of people in her life.
"You're trying to condense a story of such magnitude into four hours of television. It's difficult, and it was set over quite a long time period," Horn said.
Nick Stevens, who adapted Delia Balmer's memoir for the screen, has spoken about what drew him to her story in particular.
"As soon as I realised it was from the perspective of a woman who had survived, I was hooked," he explained (via Radio Times). "She describes her distressed, unconventional behaviour while standing in the witness box at the Old Bailey, giving evidence against Sweeney. I'd never read anything like it before."
After arranging to meet Delia to discuss the possible project, Stevens described how he felt she was "so full of mistrust and anger" but that she was "up for it from the word go, but she wanted to be sure it was an accurate depiction of her story".
The process of adapting the story for television took a number of years, and Stevens explained how he sent his scripts to Delia in that time. He said that feedback had been "mostly details" because "Delia is a perfectionist".
Balmer visited the set of Until I Kill You twice. She met with Anna Maxwell Martin briefly during filming, although not as part of any research for the role (Martin prefers not to feed this into performances when playing real characters).
"And Delia didn't meet Shaun [Evans, who plays John Sweeney] for obvious reasons," Stevens confirmed. "The production team were very deliberate about that."
Delia Balmer now: What does she think of Until I Kill You?
Ahead of the ITV series releasing, Balmer was asked whether she was hesitant to have her story dramatised.
"When I wrote my original story, I included every detail of what happened," she explained (via Radio Times). "When it came to the final attack on the doorstep, I edited it over and over again, wanting everything to read precisely as it had happened... My concern has always been to get the truth out by whatever means."
Delia recalled her meeting with Nick Stevens. "He has included some of the events which I had written about that did not appear in the book. I gave him detailed critiques of the drafts he had written," she said.
"He followed my wishes and made certain changes where possible, and as I had suggested," Delia continued. "Nick is very nice, and in his own words says he is trying to help me. The team at ITV have also treated me favourably."
ITV is airing a documentary to accompany its drama, Until I Kill You: The Real Story, on November 7 at 9pm.
Until I Kill You airs on ITV1 and ITVX from November 3 - November 6 at 9pm.
TV Editor, Digital Spy Laura has been watching television for over 30 years and professionally writing about entertainment for almost 10 of those. Previously at LOOK and now heading up the TV desk at the UK's biggest TV and movies site Digital Spy, Laura has helped steer conversations around some of the most popular shows on the box. Laura has appeared on Channel 5 News and radio to talk viewing habits and TV recommendations. As well as putting her nerd-level Buffy knowledge to good use during an IRL meet with Sarah Michelle Gellar, Laura also once had afternoon tea with One Direction, has sat around the fire pit of the Love Island villa, spoken to Sir David Attenborough about the world's oceans and even interviewed Rylan from inside the Big Brother house (housemate status, forever pending).
