White House Farm: Colin Caffell reveals the moment he started to suspect Jeremy Bamber

White House Farm has had viewers gripped since its first episode. The ITV drama, which stars critically acclaimed actor Stephen Graham and Cressida Bonas, tells the harrowing true story of the Bamber murders. In 1985, Sheila Caffell, her six-year-old twin sons and parents were tragically shot in their Essex home.

WATCH: Cressida Bonas talks about her character on White House Farm

Colin Caffell, the ex-husband of Sheila and father to twins Daniel and Nicholas, wrote a book on the tragic crimes called In Search of the Rainbow's End: Inside the White House Farm Murders and gave his permission for the story to be told. And now, Colin has opened up on the moment he started to suspect his brother-in-law of the horrific crime.

Speaking on This Morning earlier this month, Colin explained that he started to suspect Sheila's adoptive brother Jeremy after noticing his odd behaviour once he moved in with him. "I welcomed Jeremy into my flat, supported him, and gave him all of the brotherly love that I could as a victim. But then he started to show elements of him not really grieving," he explained.

MORE: Everything you need to know about true crime ITV drama White House Farm

Freddie Fox plays Jeremy Bamber in the series

"There was a point where he came running up the stairs of my flat with his hair all soaped up in spikes, he was copying the photo of Daniel and Nicholas in the bath." He continued: "And he came running up the stairs giggling and ran straight into my mother and went [back to] putting on the whole performance."

Colin revealed that as well as noticing strange behaviour around the house, Jeremy, who is played by Freddie Fox in the series, acted in a peculiar way during the funeral for their family members. "Once June and Neville and Sheila's funeral happened, we were in the car going to the Crematorium and he started larking around with Julie in the front of the car, saying what he would like to be doing to her later in the afternoon, really sick, really sick [things]," he said. "And I thought, 'There's something going on here.' Then the next thing I knew, he had been arrested for the first time, which is when I started writing the book."

Cressida Bonas plays Sheila Bamber

The series so far has seen the Bamber family deaths ruled as murder-suicide, placing Sheila Caffell, played by Cressida Bonas, as the perpetrator. At the time, Sheila, due to her mental health struggles, was reported in the papers as a 'mad murderer', something that Colin also spoke about. He told hosts Holly Willoughby and Phillip Schofield: "That was all based on people's opinions in the village, who actually didn’t know her. But she was mentally ill, she was heavily medicated for that illness. They had a spree because it had all of the elements of a glossy soap opera. They [the media] turned it into one and when I started to see the papers I thought, that's not the woman I know." In 1986 Jeremy was found guilty of the murders and is currently serving a life sentence.

White House Farm continues on Wednesday at 9pm on ITV.

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