Carey searches for one suspect, whilst Frank Napier deals withanother. As the evidence mounts, and Carey is forced to avertanother catastrophe, she begins to fear she might have made aterrible mistake. Not that Napier cares. He's using his ownunique brand of interrogation to test Carey's theory.Pierson'sfirst day on the job gets ever more challenging, but as thenet tightens for James Whitlock, it looks like SO15 might havemade a breakthrough in the case.