'Doctor Who' star Peter Capaldi is "going nowhere", says showrunner Steven Moffat.

Peter Capaldi

Peter Capaldi

The 57-year-old actor is currently winning rave reviews for his second series in the titular role in the BBC sci-fi series and although there has been speculation about him exiting the TARDIS since Jenna Coleman's departure was confirmed, Moffat is adamant he's going nowhere.

Joking about the pair's shared Scottish heritage, he said: "Peter Capaldi is going nowhere. It's a conspiracy. Piece by piece, person by person, we are replacing the English..."

Moffat has been in charge of the series since 2009 and has worked on the programme since it was brought back to TV in 2005 after 16 years off-air - with the exception of a one-off made-for-television film in 1996.

The screenwriter insists 'Doctor Who' will go on and on because it is a "television predator designed to survive" due to the ever-changing nature of the cast and style.

Speaking to Variety, Moffat, 53, said: "It's a television predator designed to survive any environment because you can replace absolutely everybody. Most shows you can't do that with ... Most shows have a built-in mortality. But here is a show that sheds us all like scales; a show that can make you feel everything except indispensable. It will carry on forever, because you can replace every part of it.

"It is definitely going to last five more years. I've seen the business plan. It's not going anywhere. And I think we can go past that. It's television's own legend. It will just keep going."