Doctor Who showrunner Steven Moffat has labelled the sci-fi series the greatest show on television ahead of his final episode at the helm.

The writer’s seven-year reign will come to an end on Christmas Day when the BBC series’ festive special Twice Upon A Time airs.

The episode, which also marks Peter Capaldi’s final outing as the Time Lord, sees the Doctor meet up with his former self, played by David Bradley, and embark on a mission alongside a World War One captain (Mark Gatiss), and assistant Bill Potts (Pearl Mackie).

Moffat said the long-running series’ ability to inspire people to become anything from scholars to scientists to artists made it the “greatest television show ever made”.

Peter Capaldi as the Doctor (BBC)
Peter Capaldi as the Doctor (BBC)

“Doctor Who by always being different can never be perfect,” he said, speaking during a panel discussion following a preview screening of the Christmas special.

“Count the hearts that beat a little faster because of Doctor Who.

“People change their view of the world and what they’re capable of because of a silly show about a man who travels around in time and space in a police box.

“So never mind the reviews, never mind the ratings, never mind any of that, count the scientists, the musicians, the scholars, the writers, the directors, the actors. Who became what they are because of this show,” he added.

Earlier, the BBC’s director-general Lord Tony Hall heaped praise on Moffat for his work on the rebooted show, first as a writer under Russell T Davies, and then as the showrunner.

Lord Hall told the audience at the Science Museum the episode was “bittersweet” due the departures of its boss and current star.

“It was 14 years ago this week that Steven Moffat was asked to write his first episode,” he said.

“And he has gone on to write over 40 more. And of course, you may not know this, but he turned down Hollywood to take the reigns as showrunner in Cardiff.

“He’s continued to surprise and delight us. He’s a master craftsman, ingenious, adventurous and great fun and I can’t wait to see what he does next.”

“Quite magical and also profound,” he added of the festive episode, which will see the first ever female Time Lord, Jodie Whittaker, regenerated as the Thirteenth Doctor.

Capaldi, who could not make the screening as he was in Scotland, sent a message apologising for his absence and thanked “everyone who loves the show for sharing it with me”.

He added: “I wish Jodie and the new Tardis team all the best for the future, and the past, and everything in between.

“I look forward to watching them journey into new places. For me it’s been an amazing trip. I went to the end of time, I met fantastical creatures and I blew them up but now it’s over, time I was off.”

:: Twice Upon A Time airs on Christmas Day at 5.30pm.