Doctor Who has regenerated for a 13th time, with Jodie Whittaker making her debut in the Christmas special.
In July, the BBC announced Whittaker would become the first female Doctor in the sci-fi series' 54-year history.
Peter Capaldi has bowed out of the role, which he has been playing since 2013.
***SPOILER WARNING***
During the Christmas episode, Twice Upon a Time, Capaldi meets with the first Doctor to save an army captain.
The 12th time lord then prepares for his regeneration, and it's Whittaker's turn to step into the TARDIS.
Capaldi transforms into Whittaker and as the regeneration finishes, she looks around and says "Oh brilliant".
A video of the regeneration was uploaded to the official Doctor Who Facebook page, alongside a post that said: "The time has come. Let the regeneration begin."
Stephen Moffat, who has been Doctor Who's showrunner for seven years, has stepped down along with Capaldi.
Whittaker has previously starred in crime drama series Broadchurch and Mr Moffat's replacement, Chris Chibnall, said he always wanted a woman to play the 13th Doctor.
"Her audition for the Doctor simply blew us all away," he said.
"Jodie is an in-demand, funny, inspiring, super-smart force of nature and will bring loads of wit, strength and warmth to the role."
On Twitter, Whovians excitedly welcomed Whittaker, while paying tribute to Capaldi.
Capaldi was asked to stay beyond his contract and while he said he was sad to leave Doctor Who, he opted to pursue something new.
"I can't praise the people I work with more highly, but I have always been someone that did a lot of different things," he said.
"I've never done one job for three years, this is the first time I've done this.
"And I feel it's sort of time for me to move on to different challenges."
Doctor Who first aired in 1963 and has become BBC's long-running cult classic.
The Christmas special will air on the ABC at 7.30pm.
