Endeavour actor Shaun Evans gives a "horribly plausible" performance in a new drama a world away from his role as the famous Oxford detective.

ITV's new four-part true crime series Until I Kill You is based on real-life events and was adapted from Delia Balmer's memoir Living with a Serial Killer.

Set in 1991, the series follows hippie agency nurse Delia (Anna Maxwell Martin), who meets John Sweeney (Shaun Evans) in a Camden pub and initially believes she has found a true romantic connection with a "fellow free spirit".

At first he would gift her flowers and showers her with affection, however, as their relationship develops, he becomes controlling and violent.

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In 1994 Delia tried to get out of the relationship but he broke into her home and held her hostage, restraining her to a bed and threatening her with a knife and a gun.

Shaun Evans has been called 'horribly plausible' as killer John Sweeney (Image: ITV)

He also admitted to the murder of his ex-girlfriend 33-year-old Melissa Halstead and two additional men in Amsterdam.

Delia eventually managed to escape, reporting Sweeney to the police again.

While he was arrested for holding her hostage, he was released on bail, before attacking Delia with an axe and severing her finger, leaving her with life-changing injuries.

It wasn't until 2001 that he was finally arrested for his crimes.

Speaking about the new series, Ms Balmer said: "My concern has always been to get the truth out by whatever means.

"I remain an angry person. Sweeney was let out on bail. The police gave me insufficient protection before his final assault. Later, I was forced to go to court to be further traumatised by the system."

Ms Balmer was also asked how she felt about the story being made into a series.

The series is based on Delia Balmer's memoir Living With A Serial Killer (Image: MultiStory Media) She said: "I wrote my own original story because I wanted the facts of what really happened known.

"Often the media had not portrayed them accurately, and many issues important to me had not been stated. The printed book had been edited and much of what I had written was also omitted."

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Mr Evans told The Guardian he "purposefully and respectfully" decided not to meet Ms Balmer.

He said: "I never met Delia or anyone connected with the case. I started to read the book then put it down because I didn't want to see the story exclusively from Delia's point of view.

"There were moments on set when you'd think: 'Bloody hell, this actually happened!' But I found I had to put that aside."

Until I Kill You continues tonight on ITV1 at 9pm and the full series is available to stream now on ITVX.