Until I Kill You: The Real Story | Preview (ITV1)

This companion documentary tells the story of Delia Balmer, a woman who bravely faced and survived the brutality of serial killer John Sweeney.

The film explores the haunting stories of Sweeney’s known victims, including American model Melissa Halstead and mother of three Paula Fields, and reveals the grisly details of how he dismembered their bodies and disposed of their remains — Melissa’s in a Rotterdam canal and Paula’s in London’s Regent’s Canal.

Narrated by Anna Maxwell Martin, who plays Delia in the gripping ITV drama series Until I Kill You, this documentary offers a raw glimpse into the real-life events that inspired the series and brings a powerful and emotive view to the story.

The ITV drama is based on Delia Balmer’s book Living with a Serial Killer, Until I Kill You was written by Nick Stevens (The Pembrokeshire Murders). In 1991, Delia leads an itinerant and solitary life in London working as an agency nurse - when she meets fellow free spirit John Sweeney in a local pub, it seems like the connection she has been searching for.

As the relationship develops, Sweeney’s artistic anti-establishment persona gives way to a darker side culminating in a series of violent attacks on Delia, during which he tells her that he killed his former girlfriend and disposed of her body in an Amsterdam canal.

Sweeney is arrested, but he is granted bail due to a catastrophic failure by the court to realise how dangerous he is. He immediately pursues Delia and subjects her to a horrific near-fatal attack - she survives, but Sweeney evades capture and disappears.

Shattered by the trauma and injuries inflicted by Sweeney, Delia bravely seeks to rebuild her life, but Sweeney returns seven years later and is arrested for the murder of another girlfriend in North London. Delia’s fragile recovery is shattered all over again as she has to face Sweeney in open court, her testimony vital to the prosecution case against him.

Until I Kill You: The Real Story airs Thursday 7th November at 9pm on ITV1.