Doctor Who showrunner Steven Moffat has said that outgoing star Peter Capaldi offered the most emotional Timelord the series has ever seen.

Moffat is also due to leave the BBC programme at the end of the current series and its Christmas special, and although he claimed “no one really cares about a behind-the-scenes person leaving”, he had plenty of fond words for Doctor actor Capaldi.

In a Facebook Live Q&A at the end of tonight’s penultimate episode, he said: “Peter only has to think at the screen and you know what he’s thinking.

Doctor WhoPeter Capaldi is almost finished as the Doctor. (BBC)

“You know the particular blend of Scottish torment he’s feeling right now.

“Despite trying to fight his emotions, he has given us the most emotional Doctor.”

Moffat continued: “It’s a hugely emotional show, which is odd for science fiction.

Doctor WhoThe actor has given an emotional performance. (BBC)

“If you don’t laugh or cry when you’re writing it, you can’t expect anyone else to.

“I look like an absolute idiot writing, I stand up for the end of the episode because it’s all so exciting that I can’t write sitting down.”

But he admitted that his last instalment of the series, due to air next Saturday, was still in the pipeline.

Steven MoffatSteven Moffat is also leaving the series. (BBC)

He said: “We haven’t actually finished episode 12 yet.

“It could be (airing) Sunday, it could be the following Thursday, I don’t know.”

Talking about life after Doctor Who, the Sherlock boss said: “I want the future of Doctor Who to be exciting because I have my place behind the sofa reserved to start watching it again.”

Steven MoffatMoffat is known for his work on Sherlock. (Chris Radburn/PA)

He continued: “I’ve got a few ideas I’d like to do that are as far away from Doctor Who and Sherlock as I can manage.”

Actress Pearl Mackie plays the Doctor’s companion Bill, who appeared to be killed off in the latest episode.

She also joined the Q&A in Cardiff, where fans were treated to a special screening of the episode accompanied by the BBC house orchestra and she talked about how the casting had affected her.

Doctor WhoMackie has been a hit as Bill. (BBC)

Mackie said: “It was my first job on camera so it’s changed my approach altogether.

“I didn’t know what I was doing before, but by the end of my first day on set I’d had more time on camera than ever before in my career.

“It has entirely changed my life, I’ve just seen my face scored by a 90-piece orchestra, that was pretty mad.

Doctor WhoMackie and Capaldi have been popular with viewers. (BBC)

“It has been a positive recognition so far – no one throws oranges at me in the supermarket, so that’s good.”

:: Doctor Who’s final episode of the series airs on BBC One on Saturday at 6.45pm.