MI5 cannot sack the officers who embarrass it, so it files them instead. The address is Slough House, a peeling building where disgraced and failed agents push paper until they give up and resign. The service calls it a posting. Everyone involved treats it as a waiting room.

[[person:gary-oldman]] plays Jackson Lamb, who supervises the place with contempt for his staff, his superiors and himself, and an insult ready for each. Jack Lowden, Rosalind Eleazar, Christopher Chung and Aimee-Ffion Edwards play the exiles still telling themselves the posting is temporary. Kristin Scott Thomas works the functioning end of the service, where careers survive. Jonathan Pryce, Saskia Reeves and Hugo Weaving supply the older generation, who remember what the job used to permit.

Will Smith, a comedian by trade, adapted Mick Herron's Slough House novels, and the comedy earns its keep. A scene gets its laugh out of somebody's humiliation and then turns into tradecraft while you are still grinning. The show treats espionage as an office problem: bad managers, thin budgets, colleagues you would not trust with a photocopier, let alone a surveillance van. If you like the Bond films but have wondered what a department's failures do on a wet Tuesday in London, this is the answer, shot grey and played dead straight by a cast that knows the joke.