Brotherly Love (3)

Beck finally breaks. He tells Fitz that he did rape Penhaligon, and then makes Fitz swear to keep it secret, which is a promise that poisons everything after it. Fitz carries it while the case comes apart around him. And the confession scene is the episode's centre of gravity, Cranitch magnificent in it. The secret sits between Fitz and every conversation he has from then on. The confession changes what the case is, and the episode never looks back.

Another prostitute is killed, and Fitz sees what the rest of the squad cannot: Maggie is the killer. The police and Father Michael protest loudly when he names her, and for a moment even he wavers. She is arrested before she can claim another victim, and the confession that follows is worse than anyone guessed. The murders were revenge on the prostitutes David slept with, the women whose trade cost the family the money that would have raised their fifth child. Michael knew about David's affairs, and he persuaded Maggie to abort that child. She never forgave him, and the grief found a target.

Maggie also confesses to the first murder, the one she did not commit, to secure David's release. The false confession does its job and lands on Beck at exactly the wrong moment, driving him past his breaking point. The climax is devastating in the way this series does best: quietly, and all at once. Robert Cavanah's Temple and Ricky Tomlinson's Wise have to watch the case slip out of procedural hands.

McGovern and Battersby close the arc without letting anyone off. David Calder's Michael and Brid Brennan's Maggie carry the weight of a family that kept its secrets until they became bodies, and the series ends its first story of the season with no clean hands anywhere. It is McGovern at his most unforgiving.