S1, E1: It's the summer holidays, but teenager Pip is focused on her school research project investigating the case of 17-year-old Andie Bell, whose disappearance in 2019 has haunted the town of Little Kilton. Andie's boyfriend Sal Singh sent a text confessing to the murder before being found dead, seemingly taking his own life. Andie's body was never found. With her own secret connection to what happened five years ago, Pip is determined to prove Sal's innocence.