To Doctor Who fans looking in from the outside, it probably seems as if taking charge of the show would be the best job on the planet. So they may have been surprised to learn recently that Chris Chibnall -– who becomes boss of the iconic BBC sci-fi series when Steven Moffat departs this Christmas – initially had his doubts about the role.

But regular series writer Mark Gatiss has now revealed his own misgivings about taking the top job, telling students of Oxford University that he sees it as something of a mixed blessing.

“To be honest, the job of showrunning Doctor Who I think is probably the hardest job in television,” Gatiss said when asked by an audience member at the Oxford Union debating society what he would have done to the series if he’d taken over from Moffat. “I’ve seen it up close.

“Steven was only 19 when he started,” Gatiss joked, “it’s taken a terrible toll on him.”

More seriously, Gatiss went on to explain that while he hadn’t been asked to fill Moffat’s shoes it wasn’t a job he thought he would suit anyway, detailing the immense pressure he’d seen his Sherlock co-creator under for the last few years.

“Honestly, it has an obvious huge appeal, but equally it’s just so completely all-consuming,” he said. “I act and I write and I couldn’t do both. I couldn’t do it if I did that.

“I wasn’t offered it. But it’s a sort of a… it’s such a poisoned chalice. It’s like the England managership, I imagine, knowing nothing about football. There’s so much expectation, such a weight of expectation, millions of people who think they can do it better than you.

“It’s a sort of relief not to be asked, to be honest. But if I had been in charge, I would have cancelled it immediately. Just out of spite! No, I don’t know. I would never have any huge plans.”

Still, Gatiss is excited about Chibnall’s new run on the series, explaining that he believes change and renewal have become built in to the 54-year-old series over the decades.

“I think it’s a thrilling notion to cast the Doctor and all those things that come with it, and I wish Chris all the luck in the world. It’s a very exciting time,” he said.

“It’s also difficult – you say goodbye to something, it’s always the end of a chapter. I’m very sad [current Doctor] Peter [Capaldi] is going, I’m sure Steven will find it a terrible wrench, how can you not after all these years? But equally, the freshness and the renewal, the regeneration if you will, is exactly what’s made the show what it is.

“And weirdly, I think if [First Doctor] William Hartnell had been well enough Doctor Who might have run for five years and then come off, which is a strange thought isn’t it? That actually maybe somehow in its DNA there is this perpetual renewal.

“I’m very excited about watching it without knowing anything at all.”

Doctor Who continues on BBC1 this Saturday 17th June at 6:45pm