Two-part Channel 4 crime drama. Frank Agnew (Mark Strong) is a law abiding detective at Blackmoss CID in Edinburgh. However, when his girlfriend Sinada goes missing, his colleague Joe Geddes (Brian McCardie) informs him that his corrupt partner Brendan McCann (John Sessions) has murdered her and so Agnew, with Geddes' help, takes revenge. As the plot thickens, it occurs to Agnew that Geddes may have had his own reasons to want McCann dead, and when another body is discovered horribly mutilated in the boot of McCann's car, Agnew soon finds himself leading an investigation into a spate of murders, one of which he himself committed. The plot thickens further when Agnew receives a phone call from his 'dead' girlfriend's mobile and he realises that she may not actually be dead after all.