Doctor Who: The Doctor's Regeneration Episodes Ranked Worst To Best

You can understand why Steven Moffat found it "monstrously stressful" writing this monumental episode. He had to find the right balance of celebrating the culmination of 50 years of adventures in time and space, but not revere it too much that it came off as just a self-satisfied, nostalgic episode.

Moffat, overall, pulls off a masterstroke. He adroitly follows his own brief that "this should be the first step on the next journey" by morphing the initially pointless Zygon subplot into a thrilling and thought-provoking two-parter with the Twelfth Doctor in series 10. Of course Chris Chibnall journeyed further than anyone in The Timeless Children.

Matt Smith and David Tennant are a delightful combination who evoke a sense of Morecambe and Wise in terms of effortless and feelgood chemistry. Moreover, John Hurt said to Smith that he and Tennant "should do a revue together".

As for Hurt? He portrays the battle weary War Doctor with understated effectiveness, leaving you feeling compassionate towards him and less a sense of dread as do his future midlife crisis selves. It's highly recommended that you listen to the excellent War Doctor audio series by Big Finish, which flesh out the character.

The only grumble is the saving of Gallifrey. Had the Doctors pushed the red button, it would've given the denouement a more powerful - and justifiable - emotional resonance, al la the Tenth Doctor's fateful decision in The Fires of Pompeii.

Farewell Captain Grumpy. Hello potentially conspicuous ears: it's obviously the bad cuppa that makes the Doctor begin to change into someone who looks remarkably like the Ninth Doctor.