Producer Peter Norris promises something special as the powerful police series comes to the end of its run. "The BBC have committed themselves to a third series, he says, before adding with a touch of mystery, "but it will have to be different because of questions left unanswered in this episode and the climactic end to the programme."

Series creator J.C. Wilsher writes the conclusion of this two-part story in which the Complaints Investigation Bureau's Tony Clark is still trying to nail his former boss, John Deakin.

But for Clark the real trouble is Trevor Bull, a victim of a police shooting years earlier. Bull is being put under pressure by both Clark and Deakin and this time he is not taking prisoners.