The Mad Woman in the Attic (2)

Another murdered woman turns up, and Fitz is ordered off the case before he has properly started. And being ordered off is the one thing guaranteed to make him want in. He and Penhaligon keep digging anyway, and the investigation keeps circling the same stubborn fact: Kelly still cannot remember the murder he is supposed to have committed.

Then a man claiming to be Kelly's priest tells Fitz something that changes the shape of everything. Kelly confessed his guilt, the priest says, some time ago. A confession should settle a case. Instead it unsettles Fitz, because the more time he spends with Kelly, the less he believes in the man's guilt. Fitz takes Kelly into his own custody, which is not procedure and never has been, and tries to work out which version of events is real. The custody arrangement is Fitz's own invention, and it gives the episode its odd, tense domestic quality. The priest's visit is the hinge of the whole story, and the episode hangs everything on it.

Adrian Dunbar's Kelly is the centre of it, a man made of gaps and silences. Around him the usual machinery turns: Billborough, Beck, Giggs, Jones, the pathologist counting the bodies. Alan Partington and Romy Baskerville add the Hobbses to the list of people touched by the killings, and Paul Copley's pathologist does his grim sums without comment. The Hobbses matter because Kelly's story has to have a world around it, and the show supplies one.

McGovern and Winterbottom keep the doubt alive from one scene to the next. Everyone in this episode is certain about something, and almost all of them are wrong. It is also the episode where the show announces that its suspects can be telling the truth, which is a rule most crime shows never learn. It is the quieter half of the pair, and all the better for it.