Does having another Doctor around change the way they react to monsters and peril? Is one luckier with the ladies? What is it like returning to Doctor Who and what makes different to other TV shows?
Discussing the differences between their respective Doctors, Matt Smith and David Tennant share what makes theirs special, what they love about working together and what makes them envious of their counterparts, in this: a look behind-the-scenes of The Day of the Doctor.
And let’s hope the two get to meet up again for future anniversaries!