Operation Edzell is largely considered one of the UK’s biggest and most catastrophic police operations. 

The operation was at the heart of the high-pressure police investigation into the devastating murder of 23-year-old Rachel Nickell on 15 July 1992. Nickell, a mother-of-one, was killed in broad daylight on Wimbledon Common, where she was walking with her two-year-old son, Alexander.

In order to find her killer, ‘Lizzie James’ an undercover female police officer, was tasked with forming a relationship with the then-suspect, Colin Stagg – and get the evidence the police need to convict him.  

Now Channel 4 has dramatised the events in their new true crime series, Deceit.

Starring Niamh Algar, Nathaniel Martello-White, Line of Duty star Rochenda Sandall and Eddie Marsan, the four-part drama “enters a dysfunctional world, where a female undercover officer, codename ‘Lizzie James’, is asked to become sexual bait for a suspected killer,” according to the show’s synopsis.

Rachel Nickell’s body was found on Wimbledon Common by a passer-by, as her young son clung to her body, saying: “Wake up, Mummy.”

Following the crime, concerns grew that, despite interviewing 32 men, the police weren’t making enough progress with the case. Their only suspect was a local oddball, Colin Stagg, who was first identified by a Crimewatch phone-in. 

The lead on the case, Detective Inspector Keith Pedder – played in the drama by Harry Treadaway – then worked with criminal psychologist Professor Paul Britton (Marsan), to draw up a profile of the man.

In the series, this sees ‘Lizzie’ claim to have murdered someone and taken part in a satanic ritual, because it was believed this would appeal to his unusual sexual perversions and he would confess to Rachel’s murder.

The psychological toll of catching a “killer”

The lengths ‘Lizzie’ had to go to during Operation Edzell were extreme. As the series’ writer, Emilia di Girolamo, told RadioTimes.com, “Lizzie James was asked to become sexual bait, and was styled, coached and given a bizarre satanic backstory specifically designed… to appeal to what the police believed Rachel Nickell’s killer desired.”

While undercover, ‘Lizzie’ attempted to elicit confessions from Stagg by describing violent sexual fantasies. In released police tape recordings, she said, “If only you had done the Wimbledon Common murder, if only you had killed her, it would be all right”, to which he replied: “I’m terribly sorry, but I haven’t.”

However, Colin Stagg was innocent, but the police remained obsessed with the wrong man.

As di Girolamo explained, “‘Lizzie’ was encouraged to verbally push further and further in her interactions with Stagg – whom she believed was a violent killer – the toll on her own mental health and wellbeing was devastating.”

Set against a backdrop of the “complicated and toxic sexual politics of the early 90s,” where there were few female officers in high-ranking positions, Deceit explores the power dynamic of being a woman trying to prove herself in a male-dominated environment – and the catastrophic effects that pressure can have.

‘Lizzie’, who is named in the series as Sadie Byrne (though this is entirely fictional) is left traumatised after having to seduce a “killer”. She is continually pushed closer and closer to Stagg, even though she believes there is a high chance she could be his next victim.

However, Rachel Nickell’s true killer was Robert Napper, who “had long-standing mental health issues rooted in the trauma of his own childhood, which are believed to have culminated in more than a hundred violent sexual attacks on women and three horrific murders,” as described by di Girolamo.

“Catastrophic and systematic police failings meant Napper escaped detection numerous times, and when he killed Rachel another innocent man, Colin Stagg, became the sole focus of the police investigation.”

“There was a devastating impact on all involved”

Executive producer of the show, David Nath said: “Colin Stagg spent 16 years as the subject of innuendo, suspicion and vilification. Talk to people now and mention the name Colin Stagg and a lot of people will say he was convicted for Rachel’s murder. He wasn’t.”

Stagg received damages and an apology from the Met for the 14 months he spent in custody around his trial.

The real life ‘Lizzie’ also sued the force but received just £125,000. But after the psychological trauma she had suffered in Operation Edzell, she was also given early retirement and granted life-long anonymity.

Deceit airs on 13 August at 9pm on Channel 4.

Images: Crime and Investigation UK/ Channel 4