Holmes and Proctor investigate the rape of a woman inside a mental health facility. After discovering a separate attack occurred at another facility six months earlier, DS Acton from Park Rise Station is seconded to Sun Hill to help investigate both cases. A staff member from the other facility claims Acton had a relationship with a nurse, Ken Forbes, who moved from the facility where the first attack occurred to the second. After Forbes uncovers a condom in the victim's room, Proctor is infuriated that he has corrupted the evidence. As Forbes is implicated by a security guard who spotted his car at the time of the attack, Proctor and Acton arrest him, and a besotted Proctor ignores Forbes protesting that Acton planted a screwdriver with paint at the scene. As the guard reveals he saw Acton at the scene scraping something off a window, Proctor realises the plant allegations may be true.