To Say I Love You (1)

Fitz's marriage has been coming apart all series, and here it comes apart in public. He is arrested outside his in-laws' house and taken to the station, which is where he meets Sean Kerrigan and Tina O'Brien. They are car thieves, young and already lost, dangerous together in a way that seems to surprise even them. They are about to turn a quiet domestic embarrassment into something much worse.

The pair is pure Bonnie and Clyde, two social outcasts who found each other and decided the world owed them a spree. Fitz, stuck in the station with his own mess, ends up in their orbit, and the episode shuttles between his wrecked home life and their escalating violence. Keith Ladd and Patti Love are the Brien parents, David Haig's Graham and Gavin Muir's Cormack orbit the trouble, and Susan Vidler's Sammy keeps the edges of the story busy. The police station is its own little world, all fluorescent light and people waiting to be interviewed, and Fitz is stuck in it at the worst moment of his week. The in-laws' house, with its neat front garden and its silent accusations, does more work than a page of exposition.

Jimmy McGovern wrote it and Andy Wilson directed it, and the change of gears is deliberate: the domestic scenes feel small and sad, the criminal scenes feel like a car heading for a wall. Susan Lynch and Andrew Tiernan give Sean and Tina a wired, frightened chemistry that makes them hard to look away from. And Fitz keeps trying to do his job in the middle of it, and the episode keeps making that job impossible. McGovern has a gift for writing people who are one push away from catastrophe, and this pair are his purest example.

The title sounds like a promise. It plays like a threat, and everyone in it is running out of room.