"We finished [filming] about two months ago. We had three different Doctors in here and we shot on 3D as well." Questioned by the "Royal", Jenna elaborated: "Yeah, three different Doctors. John Hurt, and David Tennant was back and Matt. Three different Doctors playing against each other."
Matt Smith also told Mrs Prince of Wales that the 2013 Christmas Special was his "last hurrah".
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