When does Slow Horses return?

Slow Horses is a spy thriller television series based on the 2010 novel of the same name. The first series premiered on Apple TV+ on 1 April 2022, with the second series premiering later in 2022. In June 2022, the series was renewed for third and fourth series.
British MI5 officer River Cartwright is exiled to Slough House, an administrative purgatory for service rejects. Cartwright and his colleagues must endure dull, paper pushing tasks and their miserable boss, Jackson Lamb, who expects them to quit out of boredom and frustration. Life in the house becomes entangled in a dangerous gambit by Regent's Park.