The new story arc began in last month’s 50th anniversary special, ‘The Day of the Doctor’.

The showrunner told DigitalSpy: “[The Doctor] has the possibility of going home – he can find Gallifrey – but it might take him a while, who knows? And who knows what he’ll do when he gets there? Get bored and run away again, I would think! But he has a mission statement.”

Discussing Russell T Davies’ decision to have the Doctor be the last of the Time Lords when the show returned in 2005, Moffat commented: “It was fascinating when Doctor Who first came back that he was this war survivor dealing with guilt and rage – that was his story. Of course, he slowly gets over that and then there’s a danger that he just becomes about… farting about a bit, which starts to take some of the baseline out of the show somehow. So we’ve given him something to pitch for.”

He also hinted at how the new story arc will develop: “It’s not like we’ll spend every episode saying, ‘I nearly found it!’ – we absolutely will not do that – but it gives him somewhere to go. The Doctor doesn’t know he’s a character in a television show – he doesn’t know he’s having adventures for our entertainment – he’s got to have something to do and that will be the thing he does.”

Series 8 begins filming later this month and is expected to start airing on BBC One in August 2014.

> Find out all the latest info on Series 8 in our news summary.

Are you looking forward to the search for Gallifrey? Let us know below…

> Buy the 50th anniversary special on DVD on Amazon.

> Buy the 50th anniversary special on Blu-ray on Amazon.

Watch the 50th anniversary trailer…