It’s this mix of high-octane action, humour – sometimes juvenile, sometimes sophisticated, always dark – and human frailty that makes Slow Horses such a compelling watch. Sure, there’s a certain familiarity about it now, but each season feels like a richly textured delight, satisfying unto itself, even more so when stacked up alongside its fellows.

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Precise plot points matter less than the overall tone, I feel. You know that Diana Taverner (Kristin Scott Thomas) is going to vacillate between wanting to crush Lamb and to reach out for his help as she seeks to move from Second Desk to head of MI5; you know Lamb is going to scold and denigrate his staff, but secretly trust them more than anyone else to do what needs to be done; you know River Cartwright’s efforts to get back into the good graces of The Park are going to inexplicably founder, again.

There are two more seasons in the works (season six will see the return of Hugo Weaving as American spy-assassin Frank Harkness), but we’re rapidly nearing the end of Mick Herron’s run of Slough House novels, on which this thoroughly entertaining production line is based, and that’s not good.

So Mick, if you’re reading – giddy-up. Get writing, and don’t spare the horses!