Deceit: A real-life story behind crime drama

On July 15 1992, a horrified nation learned 23-year-old Rachel Nickell had been murdered on Wimbledon Common – she had been stabbed to death in front of her two-year-old son.

Thursday, 12th August 2021, 5:00 pm

He was found by a passerby, clinging to his mother’s lifeless body and asking her to “wake up”.

The harrowing story dominated the headlines for months, and the pressure to identify Rachel’s murderer and see justice done was immense. However, as this eye-opening drama reveals, the lengths to which the Metropolitan Police went to catch the man they thought was Rachel’s killer were almost as shocking.

Five months after the murder, the Met was no closer to capturing the man they’re convinced was responsible. First identified through a BBC Crimewatch appeal, the cops were taking a keen interest in Colin Stagg (played by Sion Daniel Young), while the media fed what had become a national obsession, covering every detail of the case and demanding justice be done.

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Pedder, Britton, Sadie/Lizzie, Baz and Lucy

In desperation, the relatively young Detective Inspector (Harry Treadaway) leading the case called on the nation’s most famous criminal profiler (Eddie Marsan) to devise a bold undercover operation: they would find an attractive, young female officer, who would attempt to start a relationship with Colin Stagg, with the aim of drawing a confession out of him.

Here named ‘Sadie Byrne’ (Niamh Algar), the officer in question grew up under Thatcher’s reign with second-wave feminism and was determined to rise through the ranks of the boys and girls in blue. Unfortunately for her, the early 1990s brought with it an inevitable backlash in the form of lad culture, obliterating any feminist gains and putting women firmly back in their place.

Ambitious Sadie found a way to stand out from the crowd by becoming one of very few female undercover officers who were deployed in covert operations, known as Metropolitan Police Special Operations Group or SO10. Then she is offered a crucial role in the biggest murder enquiry the country has ever seen, as she is asked to adopt the persona of Lizzie, a woman with a dark secret in her past…

Anyone following the case at the time and afterward will know Stagg was innocent of Rachel’s murder. There was no forensic evidence linking him to the crime scene, and the police honeytrap, dubbed Operation Edzell, was later criticised by the media and the trial judge, who threw the case out, acquitting Stagg in September 1994.

Writer Emilia di Girolamo includes scenes of verbatim dialogue from previously unheard audio, video and written materials as part of her fictionalised retelling of events, giving viewers an incredible insight into one of the UK’s most flawed and controversial police investigations.

“The unique female perspective of Emilia’s extraordinary scripts will shine a light on one of the most shocking stories in modern policing,” said Caroline Hollick, head of Channel 4 drama.

As for Rachel’s killer? In 2008, convicted murderer Robert Napper, who was diagnosed with paranoid schizophrenia and Asperger syndrome, pleaded guilty on the grounds of diminished responsibility. Dubbed a “very dangerous” man, he was detained indefinitely at Broadmoor, while the Metropolitan Police publicly apologised to Colin Stagg. Justice had finally been done.

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