Trish returns to the scene of the crime in the hope it will prompt her to remember something more about the attack, while DC Katie Harford thinks she has a strong lead when she discovers a new suspect who doesn't have an alibi. Cath reveals interesting new information about the night of her party, while a match is made for the male DNA found on Trish. An unknown woman walks into the police station.

The crime drama continues. New information forces Hardy and Ellie to re-evaluate the case.