The brutal murder of Sadie Hartley is the focus of The Detectives: Inside The Major Crimes Team on ITV tonight.
It's the third and final episode of the ITV series, which has been following how detectives from Lancashire Police investigate serious crimes like armed robbery, rape and murder.
Airing this evening from 9PM, The Detectives are tasked with solving the shocking stabbing of Sadie Hartley.
The show follows every step as Lancashire Police investigate the violent attack which killed the businesswoman at her home in January 2016, unpicking a crime committed with what prosecutor John McDermott QC described as ‘demonic savagery’.
Cameras follow detectives as the case unfolds from the crime scene to the dawn raid in which key suspect Sarah Williams was arrested, and the moment the murder weapon and other key evidence is discovered and ultimately to the arrest and conviction of the key suspects.
Piecing together evidence, Police discover that Sarah previously had a relationship with Sadie’s partner and considered herself Sadie’s love rival.
The police unravel lies told by Williams and discover her accomplice, Katrina Walsh, who claims to have no memory of the crime.
However evidence showed the pair hatched an 18-month-long plan to kill Sadie involving scouting her house, visiting Germany to buy a key weapon, and even buying a second-hand car in a bid to evade detection and pull off the perfect murder.
On 17 August 2016, Sarah Williams and Katrina Walsh were found guilty of the murder of Sadie Hartley.
Both were given life sentences with a minimum terms of 30 and 25 years for Sarah and Katrina respectively.
Detective Superintendent Paul Withers, who led the investigation, said: “When somebody loses their life under such tragic circumstances I always feel for the families. It’s what drives me on if I’m honest.
"It’s imperative we get some justice for the families who are left behind, the loved ones."
The Detectives: Inside The Major Crimes Team airs at 9PM on ITV.