DI Damen Brook is on a rare period of leave to re-connect with his daughter Terri. But with her heavy drinking proving a challenge, Brook agrees to visit a local murder scene when his help is requested. An elderly couple have each been executed with a single shot to the heart with the method echoing that of a murdered middle-aged gay couple. With the same killer suspected, Brook knows that he has little choice but to cut short his leave when forced by his superiors to take the lead on the case.