39-year-old teacher Sally Wright was convicted of murder, and, although it was never proven, she was also accused of having a sexual relationship with one of her teenage students – gifted and talented Matty Taylor. Overnight her life imploded. She lost her freedom, her job as a teacher, and her marriage collapsed. Two years into her sentence, her husband filed for divorce.

Police turn the focus of their investigation toward Anna Stamp, trying to understand why she perjured herself at Sally’s trial. Anna’s boyfriend, Mark, is shocked when he accidentally discovers the real depth of Anna’s obsession with the murdered Matty. Whether prompted by resentment or genuine righteousness, Mark reports her to the police.

Police turn the focus of their investigation toward Anna Stamp, trying to understand why she perjured herself at Sally’s trial. Anna’s boyfriend, Mark, is shocked when he accidentally discovers the real depth of Anna’s obsession with the murdered Matty. Whether prompted by resentment or genuine righteousness, Mark reports her to the police.

Karen is held in custody and appears increasingly guilty. Forensics reveal fibers matching her to Matty’s jacket, and she is forced to admit to confronting the boy shortly before he died. Matty’s ruthless bullying had led to Bethan’s attempted suicide, uncovering a powerful motive for a mother to murder. And Beth’s records had been altered. As a professional social worker, Karen had access. Was altering them the act of someone covering their tracks? Was Beth somehow involved?

Matthew Taylor, a 16-year-old schoolboy, was brutally murdered in the quiet Lake District. Five years later, the accused is found not guilty and released from prison, which leaves everyone wondering who really killed him.

As Sally begins a confident return to work, the police question Anna Stamp to find out what she is hiding and, more importantly, what Matthew's parents are covering up. Karen grows increasingly paranoid over Sally and Sam.