Aired 7 November 2015

Writer Peter Harness certainly set himself up a difficult task with all of the differing plot points he set up that needing resolving at the end of ‘The Zygon Invasion,’ but he masterfully proves to be up to the task and offers one of the strongest instalments of Doctor Who in recent memory. That’s saying a lot considering how strong the entire Capaldi era has been so far. Gone is any lingering stereotype of what a family programme should and should not do, for on full display is a lesson on politics, war, and tolerance. Undoubtedly many viewers will disagree with this approach, but it’s a bold path for the programme to take, and one that it can’t shy away from forever considering how often the Doctor comes up against evil in some form. Following a clever resolution to a rather tight cliffhanger, the episode quickly picks up momentum never looks back.

Last episode, for the first time this series, Capaldi’s Doctor was not front and centre, but that is certainly not the cases this time. In fact, Capaldi unequivocally gives his best performance in the role yet, highlighted by one enrapturing monologue that grows more and more mesmerising at it continues. Kate and Bonnie both hold an Osgood box, each believing herself capable of causing mass destruction, and the Doctor simply has his words and intelligence to try to avert the end of the world. Capaldi throws his total weight into this impassioned plea, amazingly switching tone and intensity in an instant on several occasions, and after nearly ten minutes the Doctor has won with only reason in his corner. After that performance, it hardly matters that the boxes are ultimately empty.

This setup is perhaps the biggest gamble and achievement of ‘The Zygon Inversion.’ Whereas second halves- almost by rule- tend to amplify the action and culminate in a battle of epic proportions, this episode instead continues to narrow the focus and action down, culminating with conversation. The cast, scale, and locations are all dramatically reduced compared to the first part, yet the tension and stakes are clearly higher than ever. Underlining these stakes, of course, is a storyline that is incredibly relevant to the state of affairs in the modern world. Again, any programme that is willing to tackle these issues so directly, even under the guise of science fiction, must be commended, and it’s clear that nothing is being toned down for its family demographic. Perhaps most unsettling, though, is the fact that the Doctor has gone through this sequence of events fifteen times so far, all in the hopes of maintaining the Zygon treaty.

Just as Capaldi gives his best performance yet, Coleman also does her best work of this series as well. Clara’s been a bit of a lost enigma through these first few episodes, but the interrogation scene featuring Clara and Bonnie is absolutely spectacular. Coleman believably plays off of herself and continually keeps the balance of power shifting and the intense dynamic between the two shifting. Especially in the last series, and to an extent through these episodes, there has been an underlying thread of Clara becoming more like the Doctor, and the manner in which she uses her intelligence as her primary weapon in this situation is certainly in keeping with that progression.

‘The Zygon Inversion,’ then is a superb piece of television, more than equalling its opening act and speaking to the masses about very serious issues plaguing the world today. While ultimately nothing is resolved and the chess pieces are simply reset, quite possibly with a sixteenth confrontation possible, that’s almost the point in itself of the episode and shows just how much determination and hope the Doctor actually holds in his beliefs. There’s a lot more to explore in this uneasy treaty should anyone wish to do so. With strong lead performances and applications of the word ‘inversion’ in many senses right down to the format of this episode, this is certainly an episode that will be remembered as a bold and resounding success.