File on 4 tells the story behind the brutal killing of schoolgirl Brianna Ghey. She was attacked in a park near Warrington in Cheshire on a Saturday afternoon in February 2023. Two teenagers - Scarlett Jenkinson and Eddie Ratcliffe - who were obsessed with murder and torture, have been convicted of her murder. In the build-up to the killing, they exchanged text messages outlining details of their plan. The girl even wrote a detailed plan of how they would go about the murder which was found by police in her bedroom. File on 4 has discovered how she had been part of a 'managed move' to Brianna's school after she poisoned a younger girl with a cannabis-infused 'gummy' and didn't tell her what was in it. The 13-year-old became very poorly and the police were alerted. The victim's family decided against further action and the matter was referred back to the school. Scarlett Jenkinson was suspended for five days and later transferred to Brianna's school where the two girls became friends. However, before accepting Jenkinson on their register, the school was not given all the details of the incident involving the cannabis sweet. Warrington Borough Council says a child safeguarding review is underway and it will examine all of the issues - including the circumstances surrounding the managed transfer.

Reporter: Katie Barnfield