Cinema VinesApple TV’s long‑running spy comedy Slow Horses has entered its sixth season with a new, darker twist: the agency’s own former agents are being hunted down and killed. The series, which follows the bungling MI5 team known as Slough House, opens with the death of River Cartwright’s brother, David, and the funeral is cut short by the first of a series of murders that threaten to unravel the entire operation.
As the bodies pile up, the team discovers that the killings are not random acts of incompetence but part of a coordinated campaign targeting ex‑Slow Horses. Two assassins, played by Kyle Soller and MyAnna Buring, are shown methodically eliminating former members, while MI5 quietly removes the victims from its records. The first victim is Struan Loy, the disgraced operative who had been fired by Jackson Lamb in the first season.
Season six also brings back several familiar faces. Olivia Cooke’s character, Sid Baker, reappears alive after having been presumed dead since season one. Hugo Weaving’s former CIA operative, Frank Harkness—River’s estranged father and a mercenary who caused chaos in season four—returns to the fray. Kristin Scott Thomas’s Diana Taverner, now First Desk at MI5, finds herself caught in the fallout as the investigation deepens.
Showrunner Gaby Chiappe has crafted a narrative that forces Lamb and his ragtag team to confront why MI5’s discarded spies have suddenly become targets. River, played by Jack Lowden, is still grieving David’s death while dealing with relentless danger, being chased, shot at, and thrown into increasingly absurd situations. He also finds himself rekindling a romance with a former flame, adding personal stakes to the chaotic plot.
The season consists of six episodes, each running between 45 and 60 minutes, and continues to showcase the series’ signature blend of humour and bleakness. With a cast that includes Gary Oldman, Jack Lowden, Kristin Scott Thomas, Olivia Cooke, Hugo Weaving, Saskia Reeves, Christopher Chung, Rosalind Eleazar, Aimee‑Ffion Edwards, Tom Brooke, and Lenny Rush, Slow Horses Season 6 promises to keep viewers on edge as the team battles both external threats and their own internal dysfunction.
