The Scottish actor - best known as Malcolm Tucker in 'The Thick Of It' - replaces Matt Smith in the role, and has promised a 'darker, less user-friendly' version of the Doctor than we've seen before.
It has also been confirmed that Peter has already signed up to play the Doctor for a second series - and we're not surprised as the 56-year-old actor says it's 'the best role on TV'.
“[‘Doctor Who’ is] the best job on telly as far as I’m concerned," he said. "It’s so exciting and you’re working with people who are so talented and gifted.
“I mean, there is no other programme where you can find yourself facing men dressed in rubber suits playing monsters with ray-guns and all the rest of it… and meet historical figures, it’s a gas.”
But, what do we know about the 12th man destined to step into the Tardis and take a worldwide fanbase on a multi-directional voyage through time?
Prepare to become an expert as we present you with everything you need to know in 90 seconds...