The Great Detective

A convicted armed robber confesses to more robberies, and one of them is a job Peter Hoskins has already served eighteen years for. That kind of confession lands on Clark's desk with a thud, because the officer who put Hoskins away, Detective Chief Superintendent Trevor Dunne, is one of the most respected detectives in the Met, recently cleared by an enquiry. Clark is torn between duty and loyalty, and the episode makes him sit in that discomfort.

Nicholas Martin wrote it, Peter Smith directed, and the complications keep coming. Hoskins claims he has a videotape of Dunne accepting a bribe, left in a railway station locker. The tape is found. But then Clark catches Naylor trying to remove it to protect Dunne, and it emerges that the locker key was never in Hoskins's possession, and that Commander Sparrow, the man pressing Clark for a quick result, visited Hoskins in prison. Every answer opens another question.

Ian McElhinney, later of Game of Thrones, plays Dunne with the quiet authority of a man who believes his record should speak for him. Peter Blythe plays Commander Sparrow, the man pressing for the quick result, and Glyn Grain's Hoskins is the convicted robber whose confession set everything moving. Between them they frame the two pressures of the hour: the need for closure and the refusal to let a question drop. Tom Georgeson's Naylor is the episode's wounded heart, his loyalty to a hero colliding with what he knows is right.

The title is the giveaway. The great detective is exactly the kind of figure this show exists to take apart, and it does so carefully, piece by piece, without enjoying the demolition. Duty and friendship rarely make the same demands, and the episode leaves both of them dented. The railway station locker is a lovely bit of staging, a public place hiding a private accusation, and the episode milks it without overplaying it. The question of who put the tape there, and why, keeps the hour moving even when the interviews slow down.