What happened to John Sweeney? The true story behind ITV drama Until I Kill You

ITV's new drama Until I Kill You has captivated viewers since it aired earlier this week - but how much do you know about the real John Sweeney? The drama is based on a memoir written by retired nurse Delia Balmer who survived a violent relationship with convicted serial killer John Sweeney.

Delia Balmer, played by Anna Maxwell Martin in the show, first met Sweeney in a London pub in the 1990s, and the pair hit it off over their shared love of travelling. But Sweeney was hiding a dark secret having killed one of his previous girlfriends, Melissa Halstead.

Sweeney soon began to emotionally and physically abuse Delia, eventually unleashing a near fatal axe attack on her in which he severed one of her fingers. John Sweeney was eventually brought to justice for his crimes - but where is he now and what has happened to him since?

READ MORE: Who is the real Delia Balmer? The true story behind the new ITV drama Until I Kill You

Who is John Sweeney?

Liverpool-born John Sweeny is a convicted serial killer who brutally murdered former partners Melissa Halstead and Paula Field. A carpenter by trade, Sweeney murdered American model and photographer Melissa Halstead in Amsterdam.

In 1994, John broke into Delia's house after she had broken up with him and held her captive for four days, threatening her with a gun and knife. He confessed to Delia that he had dismembered Melissa and remained with her body for several days before disposing of it in a canal.

Delia managed to escape and reported John to the police for kidnapping her, but whilst on bail, he attempted to murder Delia with an axe. She only escaped thanks to a local neighbour who attacked John with a baseball bat.

John Sweeney went on the run for six years. In this time, Sweeney murdered Paula Fields - a mother of three from Liverpool. Her remains were discovered in Regent's Canal in 2001.

When he was eventually arrested in 2001, he was given four life sentences for her attempted murder, and for having four guns in his possession. Whilst investigating the case, police uncovered a hoard of more than 300 violent and pornographic paintings and poems at the filthy squat where Sweeney lived.

Where is John Sweeney now?

John Sweeney, who is now aged 67, is in prison, where he will remain for the rest of his life. He refused to leave his cell at Belmarsh prison to attend the hearing of his sentence after being convicted of both murders.

During his trial, Judge Mr Justic Saunders said: "These were terrible, wicked crimes. The heads of the victims having been removed, it is impossible to be certain how they were killed. The mutilation of the bodies is a serious aggravating feature of the murders."

He continued: "Not only does it reveal the cold-blooded nature of the killer, but it has added greatly to the distress of the families to know that parts of the bodies of their loved ones have never been recovered. Why the killings occurred, I cannot be sure, but I am satisfied that this defendant is controlling in his relationships with women and, chillingly, that control extends to deciding whether they should live or die."

Authorities believe he may have killed three more women between 1970 and 1990.

Until I Kill You continues on ITV at 9pm tonight (November 6) and The Real Story runs at 9pm on November 7.