This thrilling police drama returns as the elite squad of detectives begin investigating a string of murders with<br/>links to the police force. Could the killer be a fellow officer? The case has deeply personal ramifications for<br/>the team led by DI David Bradford (Hugo Speer, Father Brown), involving DS Vivienne Cole's (Sharon Small,<br/>The Inspector Lynley Mysteries) ex-husband and threats to DC Rob Brady's (Bailey Patrick, Bridgerton) family.<br/>As they try to discover if a murderer lurks among their ranks, the detectives also investigate the death of a schoolboy that could be connected to a girl's suicide, a widow who somewhat suspiciously refuses to grieve, and the fatal attack on a locksmith that harks back to the manslaughter of Trainee DC Billie Fitzgerald's (Tori Allen-Martin, Unforgotten) father a decade earlier.