Doctor Who completes its biggest story line in season 10, as the Doctor's newest companion steps into the spotlight.

For the last two weeks, Doctor Who has been dabbling in the second longest story line of the season. Though, to be fair, the longest story line has been only half of one, since the question of the vault and Missy's place in it has been kept in the background for much of the previous seven episodes. As such, the ongoing plot involving the invading alien force of the Monks, their reality-warping abilities, and need to be loved has become season 10's most ambitious effort so far. It's been a strange ride, coming on the heels of the Doctor losing his sight, and then becoming the answer to that problem all while creating a much larger one that's set to be explored in 'The Lie of the Land.'

Here, audiences find out what happened after Bill asked the alien invaders to restore the Doctor's vision so that he could save himself, and in doing so opened the door for the Monks to take over the planet. In an effort to make this scenario different from all the other times extraterrestrials attempted an assault on the Earth, writer Toby Whithouse, who scripted the two part 'Under the Lake' and 'Before the Flood' steps in to bat cleanup with a story of an invasion with a twist: it's already happened.

'The Lie of the Land' once again warps reality, showing a world that's not only under the rule of the Monks but is so with the Doctor apparently being complicit in their reign. It also puts Bill in the position of being the only one who knows the truth, as Doctor Who completes its longest-running story line in season 10, as the Doctor's newest companion steps into the spotlight.

Monk in Doctor Who Season 10 Episode 8

The first part of the hour revels in the strangeness of it all, illustrating how the Monks have convinced everyone they've been around forever, gently guiding humanity through its evolution and into its greatest accomplishments. It's a lot of exposition to deliver at once, but the episode implements a clever device to disseminate the information and add a layer of intrigue at the same time. The information comes in form of a broadcast extolling the virtues of the Monks, while ignoring the invaders' authoritarian regime. To make matters worse, the Doctor himself, making it appear as though he's joined with the Monks for some reason or another, delivers the broadcast. It's gaslighting through and through, and it's made worse by the Doctor's apparent complicity.

For 'The Lie of the Land' this device works because it completely takes the audience out of the typical structure of a Doctor Who episode. In addition to the gaslighting broadcast, the hour begins with Bill discussing her and the world's current circumstances with her deceased mother. The moment makes good use of what little the audience knows about Bill; at the same time it underlines the consequence of her actions at the end of last week's episode. Sure, she got the Doctor his sight back, but she also opened the door for an invading force of aliens to rule for the past six months and make everyone think this is the way the world's always been.

The effect of the dual narration makes short work of explaining the new world order, and the fact that the Monks have only been around for six months has the dual effect of putting the Doctor in a position of having already lost while putting Bill in the spotlight. It's a clever maneuver, disorienting the audience by altering the structure of a typical episode just enough to raise suspicions and create doubt that what they're seeing is really happening. The altered structure also helps give the hour a sense of finality that might otherwise have been harder to pull off, as its world-altering story line takes the tale of the Monks about as far as it can go without resulting in permanent change.

Peter Capaldi in Doctor Who Season 10 Episode 8

This being the end of a three-part storyline, there needs to be some sense that the Doctor's approach will need to be a bit unconventional in order to best an adversary capable of putting him on the losing team. As such, 'The Lie of the Land' finally enters the vault so that the Doctor and Bill can have a word with Missy. The interaction between Peter Capaldi and Michelle Gomez is quite good as the two continue to have a sparkling chemistry with one another, and Gomez's line reads are often quite funny while also drawing a certain line between her and the other Time Lord that demonstrates just how different the two actually. Still, given how much the season has been building up not only the identity of the vault's inhabitant but also Missy herself, it is somewhat underwhelming when it's revealed her role this hour is simply to guide the Doctor by illuminating for him the one path they both know he will never take.

Instead, Missy serves to give Bill the momentum for another risky decision that will potentially undo the mess the world is in thanks to (well, her decision to save the Doctor) and, as it's referred to when she, the Doctor, and Nardole reach the control center of the Monk's mothership, Fake News central. While the idea that Bill is the character making the decisions that propels the narrative forward, the explanation for why the memory of her mother overrides the fake news of the Monks' role in human history is a bit wonky, and it's made even wonkier by the Monks' rather abrupt departure from the planet and the population forgetting they were ever there in the first place.

In all, though, 'The Lie of the Land' brings the biggest story arc of the season to a close with mostly satisfying results, opening the door for more involvement from Missy, and proving that Bill can determine the course of the narrative in more ways than one.

Next: Hayley Atwell No Longer Interested in Playing Doctor Who

Doctor Who continues next Saturday with 'Empress of Mars' @9pm on BBC America.