Delia Balmer, a former nurse from London, is being featured in a Channel 5 documentary that revisits her survival story after a violent relationship with convicted murderer John Sweeney. The programme, titled I Survived a Serial Killer: The Delia Balmer Story, originally aired in 2024 and is being broadcast again on May 28, 2026, at 10pm. It focuses entirely on Balmer’s experience, using interviews, police records and expert analysis to tell the story of how she became involved with Sweeney, later known as the “Canal Killer.”
Balmer met Sweeney in a London pub in 1991 and entered into a relationship with him, unaware of his true identity or violent history. She later allowed him to live with her. The situation turned dangerous when she tried to end the relationship in 1994. According to the documentary’s account, Sweeney restrained her by tying her to her bed and threatened her with a gun and knife. In a later attack, after police restrictions had been breached, he confronted her outside her home with an axe and caused severe injuries that changed her life.
The documentary also covers the four-day period in 1994 when Balmer was held captive, as well as the attack that followed, during which a neighbour intervened with a baseball bat and helped save her life. Balmer survived both the captivity and the assault, but was left with lasting physical and psychological trauma. Her recovery took years, and she has spoken publicly about the long-term impact the ordeal had on her mental health.
Despite the abuse and violence she endured, Balmer has continued to rebuild her life. She later wrote Living With A Serial Killer, a memoir about her relationship with Sweeney and the abuse she suffered. She has also worked as a therapeutic masseuse and, over the years, has continued to enjoy dancing and travelling. One of her more recent trips was to South Africa in 2023.
Now in her 70s, Balmer is believed to live privately in London. She has not made many public appearances in recent years, aside from her involvement in the ITV drama Until I Kill You and related documentary coverage. In a previous interview with ITV, she said she still struggles with the mental health effects of the attack and the abuse she experienced.
The Channel 5 documentary presents Balmer’s story as one of survival, resilience and recovery after years of trauma. It gives viewers a detailed look at how a seemingly ordinary relationship became a nightmare, and how Balmer managed to survive one of the most chilling cases linked to a British serial killer.
