Last month Sarah Williams and Katrina Walsh were found guilty of the murder of Sadie Hartley.
A dramatic new ITV documentary tells the gripping story of how Lancashire Police solved the vicious and shocking murder - from the first call to the crime scene, through to the convictions of the killers.
The programme had extraordinary access to the police operation that brought Williams and Walsh to justice.
The Murder Of Sadie Hartley will be screened on ITV on Thursday September 1, 2016 at 9pm.
Sadie's daughter Charlotte, 23, also appears in the film and gives a touching tribute to her mother.
The Murder of Sadie Hartley, Thursday September 1, 9pm, ITV