Fresh from her trip to the States, Nikki and the Lyell unit are called in to investigate an attack against a trans man. When two further attacks are reported, one leaving a potential witness, it becomes clear that the team is facing an outbreak of violence against the trans community.

A mistake has been made during the course of the investigation, and Thomas is targeted as a scapegoat. As frustration grows between the Lyell and the acting DCI, can Thomas rally the team to gather crucial evidence to find the killer before they strike again?