The surprising decision to grant bail to Sweeney led to another attack and the killer disappeared for six years, going undetected under various aliases.

Speaking about the show and his character, Evans said: “The story we’re telling takes place over about 15 to 20 years in the life of a woman – called Delia Balmer. It’s essentially about how this woman fell victim to one of her personal relationships with coercive behavior, gaslighting, domestic abuse and violence.

“Eventually, she was let down by the court system until they really needed her as a staple in their case against the guy.

But what happened to John Sweeney and where is he now? Read on to find out.

Where is John Sweeney now?

John Sweeney is currently serving multiple life sentences for the attempted murder of Delia Balmer and the murders of Melissa Halstead and Paula Fields.

Sweeney was eventually arrested in 2001 for his vicious attack on Balmer in 1994. Balmer was only saved from Sweeney’s ax wielding and knife attack when a neighbor stepped in to attack Sweeney, prompting l to run away.

During those six years, Sweeney adopted various aliases and evaded capture by the police, but was eventually arrested after links to Paula Fields, a 31-year-old woman whose headless body was found in Regent’s Canal in London in 2001.

However, with no evidence linking him to Fields at the time, he was wanted for Balmer’s attempted murder. After giving her witness statement in court, Sweeney was found guilty and ordered to serve four life sentences.

While jailed for Balmer’s attack at Gartree Prison in Leicestershire, Sweeney was also questioned about Fields and ex-girlfriend Melissa Halstead, whose body was found in a canal in Rotterdam in 1990.

Eventually, the murders of Fields and Halstead were linked in February 2010 and Sweeney was arrested for them. Upon his arrest, several disturbing artworks were recovered from Sweeney’s prison cell in Gartree, but police also found another 300 works of art in his north London home, as well as poetry and weapons.

He was jailed for life for their crimes in 2011 by Mr Justice Saunders saying at the time: “These were terrible, vicious crimes. As the heads of the victims were removed, it is impossible to be sure how they were killed. Mutilation of corpses is a serious aggravating feature of the crimes.”

He continued: “Not only does it reveal the cold-blooded nature of the killer, but it added greatly to the families’ distress to know that body parts of their loved ones were never recovered.

“Why the murders took place I cannot be certain, but I am satisfied that this defendant controls his relationships with women and, horrifyingly, that control extends to deciding whether they should live or die.”

“I have no doubt that the seriousness of these offenses is exceptionally high and a life sentence is the appropriate sentence.”

Sweeney, who chose not to leave his Belmarsh prison cell for sentencing, was given a further 10 years in prison for perverting the course of justice.

In the trial, Sweeney continuously denied the crimes, but the jury heard how, when rejected by women, he would become violent. This was evidenced by the graphic artwork Sweeney produced, with one titled “The Scalp Hunter” depicting a woman and a bloody axe.

According to Balmer, Sweeney confessed to killing Halstead and said he killed her because he returned home to their apartment in Amsterdam to find her with two other men. He reportedly told Balmer that he shot them all and dumped their bodies in the canal, but no other bodies were found.

At the time of Sweeney’s sentencing, the Metropolitan Police were trying to find three other women who had possible links to Sweeney and were believed to be his ex-girlfriends.

Detective Chief Inspector Howard Groves, who led the investigation, said at the time: “While he is considering life behind bars, I can assure him that this investigation will continue as we seek to identify and pursue other potential victims in the UK, the Netherlands and elsewhere in Europe who may have suffered a similar fate to Melissa and Paula’.

Until I Kill You will air on ITV1 and ITVX from Sunday 3 November to Wednesday 6 November at 9pm on ITV1.

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