Thin Air (2)

Boyd's bad decisions catch up with him properly in this second half. The hunt for Joanna Gold's killer has been mishandled, and the consequences are no longer abstract: the murderer, threatened by the investigation, starts stalking her younger sister, Clara.

What follows is the kind of plan that only exists in dramas and occasionally in real life, which is worse. Clara persuades Boyd to let her wear her sister's red dress and walk out onto the Heath, bait for a stalker. It says something about how far Boyd has slipped that he agrees. The Police Commissioner hears about it and comes down on the arrangement like a ton of bricks, furious, and suddenly Boyd isn't just running a botched investigation, he's fighting for his career. Deep trouble barely covers it.

The episode handles the dread well. Sophie Winkleman gets to play Clara as someone doing a brave, stupid, understandable thing, and the sight of her in the red dress out on the grass is properly uncomfortable to watch. Roger Allam and Cherie Lunghi, as Benjamin and Leah Gold, carry the parents' side of it: a family that lost one daughter being asked to risk the other. George Calil is David Gold, Jack Ellis the Commissioner.

Barbara Machin and Ed Whitmore wrote it, Edward Bennett directed, and the regular squad is intact: Sue Johnston as Dr Grace Foley, Holly Aird as Dr Frankie Wharton, Claire Goose as DC Amelia Silver, Wil Johnson as DS Spencer Jordan, with Trevor Eve's Boyd absorbing the damage at the centre.

What I like about this one is that the suspense comes from character rather than spectacle. Boyd's flaws aren't decoration; they drive the plot, and the show is honest enough to make him pay for them. It's grim, patient, well-acted television. And it trusts you to sit with the discomfort of a family being hunted twice.