Steven Moffat confirmed he is moving on from 'Doctor Who'.
The sci-fi programme's former showrunner - who left his post in 2017 after seven years at the helm - has returned to the franchise in recent weeks on a number of projects during the coronavirus lockdown, but now he feels his time is up.
During the pandemic, he has written a new short story for Jodie Whittaker - titled 'The Terror of the Umpty Ums' - and a number of mini episodes, and he's decided to mark the end of his stint with 'The Best of Days'.
He wrote on Instagram: "Really pleased - mostly because of what everybody else did. Now. Permit me the self-indulgence.
"I planned to leave with The Husbands Of River Song. Then it was The Doctor Falls. And then it was Twice Upon A Time. And then I novelised Day Of The Doctor and that was going to be the very end.
"And then Chris got me to write "Terror Of The Umpty Ums" and Emily got me writing online minisodes.
"But this - THIS - finally ... is ... IT! Bang! Kerpow! I'm out of here! So with that in mind can I just say ... the title is quite perfect. (sic)"
'The Best of Days' is a short scene which sees Pearl Mackie and Matt Lucas reprising their respective roles as Bill and Nardole.
The special episode referenced both the ongoing Black Lives Matter protests and the coronavirus pandemic, and there was also a potential tease of a reunion between Bill and Jodie Whittaker's Time Lord.
Despite his recent involvement, Moffat had previously played down the chance of returning to pen an episode of the series itself.
He explained: "I've always said, and Russell [T Davies] has always said, I'll come back when there's an emergency. Well what do you call this?
"But no, I think that 'Doctor Who' has to change hands and have new creators, new people involved.
"And remember, I wrote a ton of them! I think I'm out of ideas. I don't have a single one left."
Tagged in Matt Lucas Jodie Whittaker Steven Moffat