Matt Smith's Doctor Who regeneration scene with Peter Capaldi is "brutal" and "traumatic," according to actress Jenna Coleman. Smith makes way for the 12th Doctor Capaldi during the Doctor Who special on Christmas Day.

Matt Smith Doctor WhoMatt Smith Regenerates Into Peter Capaldi On Christmas Day

Coleman spoke about the regeneration during an appearance on ITV's Daybreak this morning (November 19).

"I knew it was going to be sad, but it was really traumatic," Coleman said. "It was very emotional and overwhelming," she explained.

"It's a strange thing [but] it's the nature of the show," she added, "Matt leaves, Peter arrives in his costume and the scene carries on. You just keep going - that's the show."

Doctor Who's 50th anniversary special The Day of the Doctor will air on BBC one on Saturday (November 27) whilst being simulcast worldwide and screening in cinemas around the globe.

Jenna ColemanJenna Coleman [L] as the Doctor's Assistant

Capaldi, 55, was the big-favourite to take over from Matt Smith when the young star announced his departure from the show earlier this year. Recently, show boss Stephen Moffat let slip the details of the Scottish actor's contract, saying he will star in two series of six episodes each - a new deal will depend on his popularity.

Should Capaldi move on after just two seasons, he will match the quick-fire Doctor Who stint of Christopher Eccleston - something that frustrated fans.

On why the team choose The Thick of It actor - who is considerably older than Smith - Moffat said: "We couldn't have had another quirky young man because Matt had nailed the part.Peter's already a bit of a national treasure, an incredibly skilled, fine actor.

Matt Smith David Tennant John HurtMatt Smith [L], David Tennant [C] and John Hurt [R] in The Day of the Doctor

As most people have realised, the moment you think of him in the part, you find it hard to think of anyone else," he explained, according to the Express. 

Before Peter Capaldi's reveal, the 30th anniversary show will feature the return of the 10th Doctor, David Tennant, former assistant Rose, played by Billie Piper and veteran actor John Hurt. 

David Tennant Doctor WhoEverybody's Favourite Doctor Who, David Tennant