Every Doctor Who Christmas Special Ranked From Worst To Best

13. The Next Doctor (2008)

Shortly before The Next Doctor aired, David Tennant announced his intent to leave the show after a forthcoming set of specials. And with an episode concept that hinted at a future regeneration (even Tennant and then-showrunner Russell T. Davies kept teasing the Eleventh Time Lord), The Next Doctor was a curious proposition going in.

But it just didn't live up to its potential. The biggest problem here is that the mystery of David Morrissey's Jackson Lake - the "next Doctor" of the title - is wrapped up with half of the episode still to go, leaving the second half to focus on a naff gigantic Cyberman trampling across London, which feels completely at odds with the small-scale human story of Lake and the loss of his wife, which was explored in the first half.

The result is a very disjointed plot, one that Davies clearly struggled to sustain for the full hour. It feels like a missed opportunity too, because so much more could have been done with this concept. Why not leak a credible rumour that Morrissey had been cast as Eleven, just to give the episode some more weight? The two leads have fantastic chemistry and the mystery is intriguing while it lasts, but the possibility of Lake being the actual next Doctor just comes off as an underdeveloped gimmick.