Slow Horses has proven to be one of Apple TV+'s more successful shows, but the streaming service seemingly already has its replacement before seasons 4 or 5 are even released. The British spy thriller television series, run by Will Smith, is based on Mick Herron's Slough House book series, with season 1 adapting 2010's Slow Horses, season 2 following 2013's Dead Lions, and 2016's Real Tigers serving as inspiration for season 3. However, Apple TV+ is evidently happy with the show and is extending its partnership with Herron outside Slow Horses.
https://screenrant.com/slow-horses-apple-tv-down-cemetery-road-show-replacement/