Steven Moffat 'threw away' first draft of new Doctor Who episode

Steven Moffat totally scrapped the first draft of his new 'Doctor Who' episode.

The 62-year-old former showrunner - who first wrote for the BBC's iconic sci-fi series when current boss Russell T Davies revived the show in 2005 - has penned this weekend's episode 'Boom' for Ncuti Gatwa's first series as the Doctor, and it's been a long time coming.

He told the BBC: "It was quite a long time ago, around two and a half years.

"I just started tentatively writing and got about 12 to 15 pages in, and realised I had got it completely wrong.

"I started the story in the wrong place, on the wrong foot, so to speak. So I threw that away and started again."

Steven - who led the show during the Matt Smith and Peter Capaldi years - admitted he hadn't "even told the production office" that he had been writing more 'Doctor Who'.

He added: "So when I sent it to just Russell he was quite surprised - he didn’t know I had been working on it.

"Mainly, it felt pretty good and pretty familiar to be back on the TARDIS. It doesn’t seem that long ago since I was writing for Capaldi."

He explained there are challenges writing for the legendary programme, which "different jeopardy" every time, and a lot of emotions to try and balance.

He said: "It’s always hard to do Doctor Who, I think your every power of invention is stretched to the limit on 'Doctor Who'.

"Every time he steps out of that TARDIS it’s a new world, different place and set of characters, there is different jeopardy.

"It’s got to be funny and you’ve got a lot of exposition, it has to be thrilling, and you have to wrap it all up in 45 minutes – it’s the full workout every time.

"You can’t just say ‘What do we normally do?’, because there is no normal."

Steven is "always" thinking of new stories, including "day dreaming" potential 'Doctor Who' plots, even if they never see the light of day.

He added: "It’s fine that I never write them, I don’t mind that they are just something to entertain me on a tube ride."