Review: Doctor Who - The Zygon Invasion

There's double trouble in 'The Zygon Invasion'. But was it just a copy of a great Doctor Who episode or the real thing? 

'We have a Zygon revolution on our hands.'

Back when 50th anniversary extravaganza 'The Day of the Doctor' first aired, my only real gripe with the near-perfect episode was the lack of a resolution to the Zygon invasion plotline. Yes, the Doctors brilliantly got the humans and Zygons to form a peace treaty but we really needed to see how that turned out. Well, now this has finally been rectified, turning that open end into a far-reaching prologue to this story made two years later. Things like this remind me just why Steven Moffat is the best man for the lead Who job. 

In 'The Zygon Invasion' we learn that 20 million Zygons have been peacefully integrated across the world - and, unusually for Doctor Who we get a visual feel for that as well as the episode trots across the globe as much as a Bond film, giving the story a huge scale. In fact, everything is ramped up here. Despite being two episodes long, the story throws you into the action straight away and maintains a brisk pace throughout, meaning its quite a shock when the episode seems to end so soon. 

Thankfully, it has a depth to go with the scale. Firstly, it's an ingenious inversion of the classic alien invasion story (though I suppose War of the Worlds did the 'the aliens are already here' thing first, with the Tripods being buried underground...), something that is used to draw parallels to real world issues. These allusions to current affairs were mostly well-handled and certainly added an unusual political layer to a Doctor Who episode, however there were points when things were a little too on the nose, such as the Zygon language heavily resembling Arabic.

Even more than the return of the Zygons (who are rightly not overused by they way, which keeps their wonderful design threatening and unfamiliar), the biggest talking point of this episode is the resurrection of Osgood. Thankfully given the impact of her shocking demise in 'Death in Heaven', her reappearance isn't just fan-baiting and she is in fact a cornerstone of the drama in a way the character hasn't been before - the mystery of whether she is human or Zygon, just as we wonder that about everyone on screen, is the central theme of the plot. With her we also get another instance of a 'hybrid' and an enemy within a friend, running themes that are being carefully woven into each episode rather than feeling tacked-on, such as other recent story arcs. 

On the whole, of all the part ones this year 'The Zygon Invasion' is probably the most dependent on its following part (I say without having seen it) but it is still an impressive, ambitious piece on its own. Peter Harness has certainly got a better grip on writing for the show this time around, though he still brings new dimensions to it. A story with lots of location changes, military involvement and political undertones might not be the stuff of traditional Doctor Who but intelligent sci-fi certainly is.

The Doctor reunites with Osgood - just as things turn (Os)bad.

Next week: The Zygon rebels have begun their attack on Earth, and the Doctor is the last stand of humanity's defence in 'The Zygon Inversion.' 8.00PM. BBC One. Saturday 7th November.