Despite previously stating that The Crown season 5 would end the series, creator Peter Morgan has changed his mind.
Emma Corrin, who was cast after a wide-ranging search, will portray the late Princess Diana in The Crown season 4.
The X-Files star Gillian Anderson will join Olivia Coleman and Helena Bonham Carter in The Crown season 4.
Claire Foy returns as Queen Elizabeth II in new footage from The Crown Season 2, debuting this December on Netflix.
After a two-season run as Queen Elizabeth, Claire Foy is replaced by Olivia Colman for the next two season on Netflix's The Crown.