Ralf Little has been denying he's in Doctor Who for months now – and doing a pretty bad job of it.

Speaking to Digital Spy to promote his new comedy play Dead Funny, Ralf finally opened up about his guest stint... well, a bit.

"I'm not even allowed to say that I'm in it!" he insisted. "There you go – that's what I can tell you…"

But our persistence paid off and he finally shared a little about his experiences on set, filming episode two of the new series.

"The entire experience was very cool – and Peter Capaldi is a great man," he said. "I'd met him before on various bits and pieces, but he's incredibly warm and welcoming. I've probably already said too much!"

Capaldi, of course, will be joined by a new companion for series 10 – Bill, played by The Curious Incident of the Dog in the Night-Time actress Pearl Mackie, who Little called "absolutely brilliant".

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"She's a lovely girl and a great actress - really fantastic on screen. I think she's going to be a big hit!"

Ralf admitted to us that while he wasn't particularly a fan of Doctor Who in his youth, he thinks the show has been "magnificent" since its return in 2005.

"I was in the generation where [the show] was ramping downwards – if you can ramp downwards – so I was never a massive fan," he explained.

"But I think that the reboot was magnificent... and I had connections with Mark Gatiss and Steven Moffat as well, so I'm very much fans of them and the way they write and the way that they put things together."

Little's episode, though, will be written by Frank Cottrell Boyce – who he labelled "a great Northern legend of a writer".

"Frank's a fantastic, amazing writer... who also happened to write 24 Hour Party People for [director] Michael Winterbottom [in which Little played Joy Division / New Order bassist Peter Hook]. So the whole thing felt like a nice coming together of ideas."

Doctor Who will return to BBC One this Christmas for a festive special, with the next series following in early 2017.

Doctor Who series 10 news, rumours, cast, airdate and everything you need to know

Ralf Little is currently starring in the West End revival of the comedy play Dead Funny alongside Humans stars Emily Berrington and Katherine Parkinson, as well as Ralf Little and Rufus Jones.

Dead Funny will run at London's Vaudeville Theatre until February 4. Watch a teaser clip below:

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