"Kill The Moon" follows The Doctor, Clara, and (for some reason) Courtney, Clara's problem student as they travel to the moon in the year 2049 in order to make Courtney feel special as the first woman on the moon. When they get there, they find that the Earth is in serious peril from the moons ever growing weight, which has caused havoc with the tides, sinking major cities and resulting in Earth sending a small crew of astronauts to the moon in order to destroy it.
"Kill the Moon" is very much an episode of two halves, each with a distinctive tone that separates the episode neatly. The first half of the episode is quite obviously inspired by Alien, and it's done incredibly well - the main threat is a swarm of spider/facehugger like creatures that are incredibly creepy and feel genuinely threatening. Each scene in this part of the episode is directed as a horror film, with a focus on building tension and keeping viewers on the edge of their seats. It's worth mentioning that the design of the spider aliens is absolutely fantastic, tapping into a large portion of the populations mild arachnophobia to set them on edge while also using them sparingly enough that no one gets used to them, but unfortunately they end up being fairly redundant to the plot after the first half of the episode.
The second half of the episode is less horror, more drama, instead focusing on the question that the pre-opening sequence credit poses - One innocent life, or the future of mankind? - and it is here that the episode becomes controversial. To clarify, the second half of "Kill The Moon" is just as good at a purely surface level as the first in an entirely different way. The episode loses none of it's momentum in this segment and remains focused on the story at hand, providing a satisfying conclusion to the plot of the episode and a truly fantastic performance from Jenna Coleman. But the message and political leanings under the surface of this part are very, very problematic.
The next two paragraphs contain mild spoiler for "Kill The Moon".
To be blunt, everything that happens in the second half of the episode is an allegory for the ethics of abortion. This is in no way subtle - they literally have to choose whether or not to kill an unborn child, with The Doctor making comments such as "Your moon, your choice", making it as obvious as possible that this is a take on abortion. Even the throw way lines such as The Doctor assuming the President of the US in 2049 is a man before being corrected are there to try and alert the viewer to the fact that this episode is talking about issues relating to gender, and it comes off as very pro-women at a purely surface level. Clara takes the lead for most of the episode and the final decision is made by 3 female characters, with The Doctor leaving in the TARDIS until the decision is made, literally putting the future of the child entirely in the hands of women. This all follows the feminist line at this point, but the episode takes a very sudden turn in it's political leanings when the decision to abort or not is about to be made, while remaining entirely under the surface.
Characters refer to the creature inside the egg as a baby throughout in order to frame the decision as murder rather than abortion. "Kill The Moon" actually goes out of it's way to emphasise that the wishes of the "mother" (in this case, Earth) should not be taken into consideration, even when the "mother" is at risk, by having Clara and Courntey ignore the wishes of the Earth after asking for it's decision, something that later turns out to be the right thing to do, allowing humanity to progress as a species, a take on the argument that any aborted child could have one day cured cancer or done something great that advanced the human race. The Doctor claims that by not aborting, Earth can now begin to explore the galaxy, something that wouldn't have happened if they had killed the moon. The character that was all for aborting the moon actually thanks Clara and Courtney for stopping her at the end of the episode. It ends up being so painfully pro-life that it comes across as poor propaganda - it could have only been more obvious if the ship with the nuclear bombs on had of been called Planned Parenthood. It's not subtle, and it doesn't feel like the kind of thing that a government funded television show aimed at young adults should be showing.
Other than this strange message that "Kill The Moon" screams at the audience, the episode is great but not flawless. Courtney is totally redundant as a character here, serving literally no purpose while also being the most two-dimensional, poorly written character ever created. She's a combination of every bad teenager trope, which is a shame because Ellis George, the actress who plays Courtney, seems much better than the material she has been given. If Clara was to leave the series, it seems that The Doctor trying to tame a "disruptive influence" could fill at least a few episodes, again shifting the dynamic of the companion/Doctor relationship for a while.
There have been some complaints about the science in this episode, but Doctor Who's scientific inaccuracies has never been something that bothered me being as the show is basically pure fantasy masquerading as sci-fi. If you can buy a time machine that is bigger on the inside than the outside, you really shouldn't complain that the moon gaining weight doesn't make sense.
Despite a very heavy handed and controversial message underneath the surface, "Kill The Moon" is still the best episode of Season 8 so far. It's faced paced, creepy, character driven and has far reaching ramifications for The Doctors relationship with Clara, but it is let down (and potentially overshadowed) by containing such a divisive element of the story. It's nice to see Doctor Who attempt to tackle a real world issue - it shows ambition in a series that many thought was stagnant - but having an opinion on that issue is a mistake that some people may be unable to forgive, certainly a mistake that should not be made again. If this season is Doctor Who's attempt to paint itself as pro-women, then "Kill The Moon" is, quite frankly, a major cock up.