The harrowing story documenting the murder of childhood friends Holly Wells and Jessica Chapman airs tonight at 9pm on Channel 5.
The two-part show will cover the events both leading up to and after the friends' murder, alongside the motivations and history of their killer, Ian Huntley.
Episode one charts the first 14 days of the girls' disappearance, the search parties and Huntley becoming a prime suspect.
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The second episode airing tomorrow night at the same time, will cover Huntley's downfall as evidence emerges and the truth is revealed to the world.
Holly and Jessica were 10 year old school friends who both grew up in Soham, East Cambridgeshire. On 4th August as the friends enjoyed a barbeque at Jessica's family home, they set off to buy sweets from the local shop but never returned.
Originally a participant in search parties for the two, Huntley quickly became a prime suspect in their disappearance.
Huntley worked as a caretaker in a nearby secondary school, Soham Village College. During his time there he became engaged to Maxine Carr, who was employed as a teaching assistant in Holy and Jessica's school, forming his connection with the girls.
Having a history of dating far younger women, he met his ex, Katie Bryan, at 15 and quickly developed a sexual relationship with her that she called "abusive."
He fathered a daughter with Bryan but the couple split before she was born. There has been reportedly no contact between them since the end of their relationship.
At around 8:30pm, Holly and Jessica's parents became increasingly concerned about their daughters' whereabouts and called on a search party for help.
Huntley was one of those amongst the party and even spoke to police in an effort to help speed up the search.
He spoke of how he was the friends' possible last contact before they went missing, saying: "It doesn't help the fact that I was one of the last people to speak to them.
"I keep re-living that conversation and thinking perhaps something different could have been said, perhaps I could have kept them here a little bit longer and maybe changed events."
In reality, Huntley invited the girls in by claiming Carr would be there but ended up killing them both.
He claimed Holly suffered a nosebleed and while he was trying to help her, accidentally knocked her into the bath where she drowned. Following Holly's death, Jessica became hysteric and in an attempt to keep her quiet, he alleged he smothered her by mistake with his hand.
A pathologist studying these claims, Dr Nathaniel Cary, rejected this story, however, calling it "wholly implausible". It is likely both girls died from asphyxiation before their bodies were disposed of in an irrigation ditch more than 10 miles away from Soham.
Huntley became a person of great interest as both Holly and Jessica's burnt Manchester United shirts appeared in a bin at the school he worked at. It took two weeks for their bodies and evidence to be found.
The story sparked outrage nationwide and the effort to find them during the two weeks is one of the most extensive in British history.
Huntley is now 15 years into serving two life sentences.
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