The Netflix series announced on Saturday that Gillian Anderson will be taking on the role of the former British Prime Minister for its fourth season, which is now in production.
"I am so excited to be joining the cast and crew of The Crown and to have the opportunity to portray such a complicated and controversial woman," Anderson said in a statement. "Thatcher was undoubtedly formidable but I am relishing exploring beneath the surface and, dare I say, falling in love with the icon who, whether loved or despised, defined an era."
Meanwhile, The Crown season three will span the next decade of the monarchy following the series' season two ending in 1964. Olivia Colman will be playing Queen Elizabeth II, taking over for Claire Foy, who played a younger version of the royal during the first two seasons of the show and won an Emmy for the role.
Actor Tobias Menzies takes over as Prince Phillip and Emerald Fennell is Camilla Shand, who would eventually become Camilla, Duchess of Cornwall. Rounding out the cast are Helena Bonham Carter as Princess Margaret, Ben Daniels as Tony Armstrong-Jones, Josh O'Connor as Prince Charles, Erin Doherty as Princess Anne, Emerald Fennell as Camilla Shand, Marion Bailey as The Queen Mother and Jason Watkins as Prime Minister Harold Wilson.