Broadchurch star Olivia Colman will be acceding to the throne in The Crown, a series spokesperson has confirmed.
She will take over from Claire Foy, who plays Queen Elizabeth II in the early years of her reign, in seasons three and four of the show.
Foy, who has won a Golden Globe for the part, has previously said she was aware she would only be in two series.
Colman is expected to be seen in the role from 2019. It's yet to be revealed who will play her Prince Philip.
A spokeswoman for the show said the subscription service had confirmed seasons three and four and that Colman was "confirmed to star".
Former Doctor Who actor Matt Smith is currently starring as the Duke of Edinburgh.
He and Foy will soon be seen in the second series of the show, due for release in December.
"This is the last stint," Foy will be seen telling Graham Norton later in this week's edition of his BBC One chat show. "It's over, I'm done.
"I always knew it was only going to be two series and then the part would be reincarnated and someone else takes over. That's the nature of the part."
Colman, who won a Golden Globe for The Night Manager and has also appeared in BBC Three's Fleabag, will play the Queen in the years from 1963, when the monarch turned 37.
Another actress is expected to take over to play the monarch in later life.
Fans were excited by her casting, with one saying it was "amazing news".
Evening Standard TV editor Toby Earle echoed many people's opinions, saying Colman was "already the Queen".
Colman has form starring as royalty. She played the future Queen Mother in 2012's Hyde Park on Hudson and will be seen as Queen Anne in next year's The Favourite.
Netflix's drama started in 1947 with Elizabeth's engagement to Prince Philip and is expected to continue up to the present day.
Read more: http://www.bbc.com/news/uk