Though most of the surprise behind 'Doctor Who''s heralded 12th Doctor casting lay in the decision not to shake things up with a new race or gender, plenty of fans were similarly caught off guard that the 55 year-old Peter Capaldi would take the franchise away from its younger-skewing recent history. We've heard 'Doctor Who' mastermind Steven Moffat defend Capaldi's casting before, but what does he have to say on the age difference?

"The Doctor's always said he’s thousands of years old, and suddenly he’s going to look closer to what we know he secretly is," Moffat says in the latest issue of Doctor Who Magazine. "He’s going to look like an older man. A fiercer man. He won’t be the dashing young man he was a minute ago, and I think that’ll be rather exciting."

'Doctor Who' has made no secret of skewing younger over the years, starting with the initial 2005 revival series headed by Christopher Eccleston, moving into the more female-friendly David Tennant, and more recently its youngest casting yet in heartthrob Matt Smith. True, an older Doctor lands closer to the series' roots, though we can't quite shake the image of younger 'Doctor Who' fans initially brought to the series by Smith's charm and good looks, now presented with a much older man in the title role.

[Peter Capaldi]’s always looked like Doctor Who, how has this taken us so long?! Because the moment you say his name, you go ‘Of course!’ Because he’s got the hair, and he’s got the look, he’s brilliant, he’s known to be a fan, of course it’s bloody him!

The question of what took so long only grows when you consider that Capaldi actually appeared on ‘Doctor Who’ in 2008 as marble merchant Caecilius, opposite David Tennant in season 4 episode “The Fires of Pompeii.” Even more, Capaldi also appeared on ‘Torchwood: Children of Earth’ as Permanent Secretary to the Home Office John Frobisher. Oddly enough, Capaldi even played a doctor of the "W.H.O" (World Health Organization) in 'World War Z.'

Well, what say you Who-vians? Will 'Doctor Who' alienate any of its younger viewers in casting an older Doctor, or will Peter Capaldi prove his worth when the eighth series begins in 2014?

More From ScreenCrush