Gillian Anderson Will Play Margaret Thatcher in 'The Crown'

It's official: Gillian Anderson will play former British prime minister Margaret Thatcher in The Crown.

We first reported the possibility way back in August, but The Sunday Times and Deadline confirmed it yesterday (January 20) as filming continues on seasons three and four of Netflix's royal epic.

The X-Files star won't appear until season four, however, when the saga reaches the late 1970s and 1980s. Thatcher became the U.K.'s first female prime minister in 1979, and was a formidable political presence until her resignation in 1990.

But we should expect some fireworks when she does: Thatcher's weekly meetings with the Queen were reportedly very frosty. So frosty, in fact, they became the subject of The Audience, the 2013 play starring Dame Helen Mirren and written by showrunner Peter Morgan a few years before he created The Crown.

The two women reportedly disagreed over Apartheid in South Africa, the 1984-5 miners' strike and the 1982 Falklands War with Argentina, making it a challenging and formidable role for Gillian.

It also means we'll get to see her squaring up to Olivia Colman, who takes over from Claire Foy in the role of the Queen for seasons three and four. We can't imagine a better pairing - well, not since Gillian shared screen space with a certain Fox Mulder, anyway.

Season four is shaping up to be a cracker in more ways than one. As well as Gillian's casting, not to mention the wider cast of Helena Bonham Carter and Tobias Menzies, it will also cover the 1981 royal wedding, when Prince Charles (played in seasons three and four by Josh O'Connor) married Lady Diana Spencer. Deep breaths while we wait to hear who'll be playing that role.

The Crown season three is expected to launch in 2019, with season four following in 2020.

What do you think of this casting?