When a woman is found brutally murdered, evidence discovered at the scene links the murder to a 20-year-old unsolved crime. Detectives and old flames Molly McGee and Alex O'Connell are reunited after a long absence to solve the crime.

Molly's daughter Lily partakes in some risqué online activity, which Freddie manipulates in an act of revenge against Molly. Meanwhile, Molly's suspicions about Freddie's involvement in Dorothy Moxley's murder deepen.