All five episodes from the fourth series of the BBC crime drama in which a murder squad investigate complex cases in London. One of the detectives, DI David Bradford (Hugo Speer), takes the investigations more seriously when his own wife suddenly disappears. In this series, DC Rob Brady (Bailey Patrick) is arrested when a witness is found dead in his car. The episodes are: 'Wake-Up Call', 'Fallout', 'Old Wounds', 'Amnesia' and 'Vendetta'.