Channel 4's new documentary programme, Moors Murders, examines infamous serial killers Ian Brady and Myra Hindley, who took the lives of five children between July 1963 and October 1965.
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While those who tune in will learn more about the murderers through never-before-seen letters written by the pair over five decades in prison, some viewers may be curious to know more about their victims.
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Moors Murders: which victims were never found?
Ian Brady and Myra Hindley were responsible for the deaths of five children: Pauline Reade, John Kilbride, Keith Bennett, Lesley Ann Downey and Edward Evans. Their victims were aged between 10 and 17 and at least four of them were also sexually assaulted.
While four of the victims' bodies were found, the location of 12-year-old Keith Bennett's body has never been uncovered. Keith was lured into Hindley's van after the pair spotted him walking to his grandmother's house on June 16, 1964.
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Hindley drove to a lay-by on the Moor and Brady took the boy away. He returned 30 minutes later having sexually assaulted and strangled him.
Ian Brady died in 2017, never revealing the location of Keith Bennett's body
Brady finally confessed to Keith's murder over 20 years later in 1985 after being transferred from prison to a maximum-security hospital. A search was carried out years later and both Hindley and Brady were taken back to the moors to pinpoint where they had buried Keith's body.
Before he died of cancer in 2017, Brady was urged to disclose the location of Keith's body but remained silent. It was revealed that he even refused to cooperate with police on his death bed.
Myra Hindley died in 2002
Brady is believed to have written a letter to Keith's mother, Winnie Johnson, which could have been key to finding Keith's body. The Moors Murderer's mental health advocate Jackie Powell claims she received the letter in a sealed envelope.
She was arrested by the police on suspicion of preventing the lawful burial of a body and a ten-hour search was carried out at her home in South Wales. She was later released and is believed to have told the police that she had since returned the letter to Brady.
Keith Bennett's body has never been found
In December 2012, an envelope with the words "to be opened in the event of my death" written on the front was discovered by police - but with no letter inside.
Keith’s mum, Winnie, died from cancer in 2012 having never learnt the truth of where her son was buried.
The third and final episode of Channel 4's Moors Murders airs on Monday 7 March at 9pm.
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