Of course, the Doctor has to find Gallifrey first, though I suspect that they've already dropped hints in the previous seasons as to where it might be. I was thinking that the painting itself might be Gallifrey, but then I remembered that the Doctors used it themselves to get into the Black Archive.
I think/hope this is going to take some time so lots of clues to be dropped going forward however if they resolve the return of Gallifrey quickly (and I mean really quickly) then my money would be on Trenzalore. The big hint being that the Doctor(s) saying they didn't want to go there and "we needed a new destination" - it would be just like Dr Who for the place they want to avoid being the place they most want to go.
My only regret was that Hurt wasn't allowed to play the Doctor longer. He had the best lines by far and would have made a great Doctor for at least a season or two. Oh well.
I felt Hurt was sort of an amalgamation of a few classic doctors particularly in that first scene with all three. It was like the classic doctors getting a look at the new doctors.
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