Chris Chibnall will write the first words for Peter Capaldi's replacement in the 'Doctor Who' Christmas special.

Peter Capaldi and Pearl Mackie

Peter Capaldi and Pearl Mackie

The 46-year-old television writer will take over from current showrunner Steven Moffat on the popular BBC One sci-fi drama after this year's annual holiday episode, which will also mark the last outing for actor Peter Capaldi, who portrays the titular regenerating Time Lord.

But although Chris doesn't take over the position until after the Christmas special, 55-year-old Steven has given him the honour of penning the first piece of dialogue to be spoken by Peter's yet-to-be-cast replacement.

Steven told Empire magazine: "I haven't completely planned it, but I quite like the insanity of the fact this is a job you quit two pages before you type 'End Titles.'"

The decision emulates the one made by previous showrunner Russell T Davies when he stepped down from the role in 2010, as he let Steven pen the first words to be spoken by Peter's predecessor Matt Smith, who took over from David Tennant.

Meanwhile, it has also been revealed that the first episode series 10 of the long-running drama - which is due to start on April 15 - will see The Doctor and his new companion Bill (Pearl Mackie) take on the iconic villains, the Daleks.

New pictures released by the BBC reveal 'The Pilot' - which marks Pearl's debut episode as The Doctor's companion - will feature the popular antagonists, as well as a new form of the aliens which is being described as a "Wet Dalek Lady", played by actress Stephanie Hyam.

The news comes after it was previously revealed Peter would get the chance to battle his personal favourite villain, the Mondasian Cybermen, in his last series.

The villains are the original version of the familiar foes, hailing from Earth's twin planet Mondas and have not been seen in the sci-fi show for over 50 years.

The new series of 'Doctor Who' begins on BBC One on Saturday 15 April.