Boyd and his team struggle to find the truth behind the murder of a prominent Home Office adviser, when a petty criminal is acquitted of the crime. Once a prominent feminist activist, victim Katherine Reed had attacked the establishment at every opportunity, only to later switch sides. Boyd's progress on the case is hampered not only by a Home Office audit, which means the team will be shadowed throughout, but also by the fact that the original investigation was conducted by one of his old flames.

Whle facing a surprise audit from the Home Office, DCI Boyd (Trevor Eve) and the team try to continue their investigation into the murder ... but as they go on with their inquiries at Whitehall, they quickly discover the atmosphere to be very dark and secretive.