It was one of the most high-profile and controversial murder cases in the UK.
And now the investigation into the fatal stabbing of young mum Rachel Nickell on Wimbledon Common in 1992 in front of her toddler son in broad daylight has been turned into a four-part drama for Channel 4, Deceit.
And playing wrongly-accused Colin Stagg is Cardiff-born Sion Daniel Young in what is one of his first major TV roles.
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The drama, which starts on Friday, August 13, will include never before heard audio and video footage from the investigation.
A female police officer was used to set a ‘honeytrap’ for Stagg, known at the time as Operation Edzell. In the drama, Niamh Algar portrays the ambitious Met Police officer codenamed ‘Lizzie James’.
The case against Stagg was eventually thrown out and, following a cold case review, convicted murderer Robert Napper pleaded guilty to the manslaughter of Rachel Nickell on the grounds of diminished responsibility 16 years after the crime was committed. He was detained indefinitely at Broadmoor.
Talking about playing Stagg, Sion said: “Colin has an enormous journey through the series. The scripts were so detailed. They were my blueprints, as much as the audio or visual material of him.”
Sion revealed that he never met the real Colin Stagg, who was released from prison after 13 months due to the case being thrown out.
He said: “I never met him or spoke to him. I’m ultimately really glad because I don’t know what I would have gained from meeting Colin 30 years on. Instead I could home in on footage near the time, the telly stuff he did after he was exonerated and the book he wrote with David Kessler. That became my bible.”
Previously, Sion, whose age range is listed on the Sue Terry Voices website as 20s-30s, has appeared in the 2012 film Private Peaceful and the recent BBC Wales/S4C co-production Keeping Faith/Un Bore Mercher, a thriller set in Carmarthenshire.
Sion has also appeared in many theatre show, including the West End productions of War Horse and The Curious Incident of the Dog in the Night-time.
Working for National Theatre Wales, he has starred in The Radicalisation of Bradley Manning, The Village Social, and Mametz.
He has been nominated for a Bafta Cymru for Best Actor for his portrayal of Gethin in the BBC docudrama The Left Behind in 2020.
Deceit will start Friday, August, 13 at 9pm on Channel 4.
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