SAY what you like about Russell “the T” Davies, he knows how to end on a cliffhanger. And the ending to Christmas Day’s Doctor Who was certainly a doozey.

The episode as a whole, up until a minute before the end, was good rather than great. I loved John Simm as the Master, I liked the twist that his resurrection was despite his wife’s efforts, not because of them. Tennant’s acting was his best yet – almost too good for a family sci-fi show, in fact.

But the last minute of the show, in which Timothy Dalton’s character is revealed, was breath-taking. Now, a couple of concerns, here (and they are minor ones): when I started collecting American superhero comics in the ’70s, I was regularly frustrated by the practice the writers had of killing off main characters, only to resurrect them a few issues later. Superman and Captain America are two more recent examples.

So in The End of the World, the second episode of Davies’s rebooted Doctor Who starring Christopher Eccleston and Billie Piper, we discovered that in the years since the programme last appeared on our screens, the Time Wars had resulted in the complete obliteration of both sides: the Daleks and the Time Lords, leaving the Doctor the last surviving member of his race.

Except, it turned out the Daleks hadn’t just survived – they had prospered in the Time Lord-less universe. All well and good – you can’t really have Doctor Who without the Daleks. And now we have the return of the Time Lords, which is powerful and dramatic, but it leaves me asking the question: why bother with the drama of the Time War in the first place? If it turned out that neither side was wiped out, it kind of lessens the drama of the revelation in the first place, doesn’t it?

My second minor quibble may turn out to be groundless. The finale to season three, when the Doctor was rescued from the Master’s cruel captivity by the world’s population thinking nice thoughts about him (no, seriously) was undoubtedly the weakest of all the season conclusions so far. Add to the mix the clichéd and lazy plot mechanism of the “we turned back time so none of it ever actually happened” and it left a very unsatisfying sense of anti-climax.

So now, at the end of this year’s Christmas special, we have the entire population of earth having become exact replicas of the Master. An ambitious and original idea, I’ll grant. So how is this reversed? If it’s a time reversal or some such nonsense, it’ll have been a waste of a good idea. If it’s another of Davies’s famed “reversing th polarity of the neutron flow” gobbledygook, then ditto. We need a sound, logical and dramatic solution to this situation. Davies had the imagnation to invent it in the first place; surely he has the ingenuity to solve it without resorting to a lazy device the dramatic equivalent of a “reset” button?

Oh, and what’s with this nonsense of the whole of Britain talking excitedly about a broadcast from President Obama on Christmas evening?

Of course, I’m looking forward to part 2, and I’m getting prepared to have my emotions trifled with as David Tennant makes way for Matt Smith in the title role. Because if Russell T. Davies sometimes has difficulty writing his way out of the impossible situations he has himself created, there’s one thing he can write better than anyone else: drama that actually moves you.