Nancy is a detective sergeant who hides a longstanding loyalty to a haulier and drugs trafficker named Frank. When a clandestine meeting ends in murder and Nancy is caught in the crossfire, her link to Frank suddenly risks being exposed. Seconded to the murder investigation in her home town of Brighton, she finds herself playing a very dangerous game, as under the gaze of her new colleagues, Nancy must track down the killer while all the time concealing her role as the missing witness. When someone connected to the investigation is attacked and a vital piece of evidence goes astray, Nancy realises with horror that the killer is close, and may be getting inside help from the police.