English stage royalty Jason Watkins has been cast as the Prime Minister, while Gillian Anderson has been pegged as the producers choice for Britains first female leader, Margaret Thatcher.
The series is set to follow the trials and tribulations of Queen Elizabeth II's reign, with season three set to introduce Princess Diana (who will be played by Emma Corrin) and Camilla Parker Bowles (played by Emerald Fennell).
The producers have confirmed that we will meet Princess Diana in the last few episodes of the third season, but that the future first wife of the Prince of Wales will become a key player in season four.
Olivia Colman has previously admitted that the cast and crew finished filming The Crown season 3 in February, and will pick up shooting season 4 this month. The announcement hopefully confirms that fans of the epic historical drama won't have to wait too long between seasons!