Slow Horses facts: 6-episode series, 7 novels, 2 renewals

What makes Slow Horses stand out?

Slow Horses facts start with a spy series that turns failure into its engine. This British thriller is based on the Slough House novels by Mick Herron, and Apple TV+ premiered the adaptation on 1 April 2022.

The show was adapted for television by the English comedian and writer Will Smith. Apple TV+ gave it a straight-to-series order in October 2019, and filming on the first series began on 30 November 2020 in the UK.

What is Slough House in the series?

Slough House is a banishment room for MI5 service rejects who have seriously failed a task but not badly enough to get sacked. The agents sent there are known as "slow horses."

That setup gives the series its title and its pressure-cooker atmosphere. River Cartwright ends up there after a very public training-exercise blunder, joining a group of agents who have been pushed aside rather than removed from service.

Who runs Slough House?

Jackson Lamb supervises Slough House and subjects agents to verbal abuse. Gary Oldman plays Lamb, bringing the character to the center of the series.

Kristin Scott Thomas plays Diana Taverner, who was promoted to First Desk at the end of series five. Jonathan Pryce plays David Cartwright, River's grandfather and a former senior MI5 official known as "The Old Bastard."

Which books became the first six series?

The first six series adapted the novels Slow Horses, Dead Lions, Real Tigers, Spook Street, London Rules, Joe Country, and Slough House. Each series so far has consisted of six episodes.

That structure has stayed consistent across the run, giving the show a clear rhythm from one adaptation to the next. All six series of Slow Horses have received critical acclaim.

What comes next for Slow Horses?

Slow Horses has been renewed for a seventh and eighth series. Series 7 is based on Bad Actors and series 8 is based on Clown Town.

That means the television run continues well beyond the books already adapted, with more of Mick Herron's world moving onto Apple TV+. From Slough House to First Desk, the series has built its story around MI5 failures, sharp hierarchy, and six-episode seasons.

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