“Run!”

It’s the phrase that defined the RTD era of Doctor Who, and which still jogs through Steven Moffat’s tenure. But what happens when The Doctor stops running? Trouble runs to him instead: less in the shape of malevolent psychic snow and more in the form of one feisty governess named Clara (Jenna-Louise Coleman).

Following his Pond farewell, The Doctor is the bereaved grandfather, shut away in his new retro TARDIS and only venturing out into the Victorian streets to be difficult to the people he encounters. There’s a smidgen of the First Doctor in his crankiness; a demonstration of how seamlessly Smith folds past performances into his own compelling take on the Time Lord.

Along saunters Jenna-Louise Coleman who is – to retreat to a familiar catchphrase that we hope to hear again during the 50th anniversary – fantastic. Utterly fantastic. Not ‘the girl who waited’ but rather ‘the girl who waits for no one’.

Clara is completely different to previous TARDIS travellers but embodies everything you want a 21st (or even 19th) century Who companion to be, possessing a mind that whirrs so fast as to keep The Doctor on his toes and the kind of cheeky humour that serves a gal well during an alien invasion. Coleman’s chemistry with Matt Smith is instant, frisky, and clearly Steven Moffat enjoyed writing it for there’s not a word wasted. It’s going to be a true pleasure to watch her in future episodes.

However, if you think ‘The Snowmen’ is going to help melt away the enigma surrounding her character then we’d remind you that this is very much the beginning of a character’s story, not an end. Behind Clara’s endearing perkiness lurks mystery, and while it’ll keep fans tearing their hair out it injects a new energy which the show and The Doctor need.

To focus solely on Coleman and Smith’s performances would be to do a disservice to the wonderful ensemble piece that ‘The Snowmen’ is. The Demons Run gang of Madame Vastra, her wife Jenny, and their Sontaran Jeeves, Strax, are so effervescent as to demand a series all their own and fans will be delighted at how much screen time they get. The comic interplay between Strax and The Doctor alone is sure to provoke in you the feeling that surely there’s room for a Sontaran companion aboard the TARDIS.

It almost doesn’t matter that the evil alien plot afoot here is complete nonsense, nor that the talents of Richard E. Grant as Dr. Simeon and Sir Ian McKellen as the Snowman – a wicked duo we’ve taken to calling ‘Withnail & Ice’ – are woefully underused. There is such fun to be had here, so many keenly observed interactions between characters, that you’re swept away from jargon and plot holes by an avalanche of enjoyment.

This is Steven Moffat’s finest Christmas special to date but it’s also a manifesto for what’s to come; preparing us for the rest of Series 7 and the 50th anniversary with mysteries yet to be unwrapped,  teasing us with peeks under the wrapping paper and shakes of the box. The first half of Series 7 may have left some apathetic, but by the time the credits roll on Christmas night The Doctor’s ready to run again, and you will be too.

Airs at 5.15pm on Tuesday 25 December 2012 on BBC One.

> Buy Series 7 Part 1 on DVD on Amazon.

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