When a tragic communication error leaves PC Nick Bentley caught in the cross-fire of armed drug-dealers with no back-up, DS Brooks and DS Devlin investigate, and following a lead to a small-time dealer, Theo Carson. However, Theo claims a second police officer was standing nearby, doing nothing, whilst his partner bled to death. James Steel and Alesha Phillips feel the case has to be pursued, but CPS Director Castle, is concerned that pursuing such a case would be institutional suicide, damaging the delicate relationship they have with uniformed police beyond repair.