This review contains spoilers for the episode of Doctor Who.

The first true outing for Bill as The Doctor’s companion sees him take us to an off-world Earth colony, that is currently only inhabited by tiny nanobots called the Vardy and their robotic avatars that communicate via emoji. Honestly this was a premise that could have been pretty poor, emoji robot sounded like a misguided attempt to play into what is currently popular. But thankfully Frank Cottrell-Boyce managed to make his script full of great ideas that were almost Isaac Asimov in its exploration of Robots gone awry.

The idea of the Vardy misunderstanding their instructions to keep the people of the colony happy, so that this was taken to the extreme was a really interesting one. The fact that they saw human’s grief as a disease that needed to be eradicated. There was some suggestion that the Vardy were programmed this way due to the violence and wars that lead to Earth being evacuated and colonies such as this one founded. But this is only hinted at, it could have been an interesting idea to explore, but it is unlikely it could have been done properly in a single episode. The Doctor’s explanation of this through his story of The Magic Haddock was also a very nice way to make it clear what was happening.

Bill’s story this week was much more focused on her getting to understand who The Doctor was, and what his place in the Universe is. The show made good use of the ‘Advice and assistance obtainable immediately’ sign on the TARDIS’ doors as part of the how Bill comes to realise what we all know, that The Doctor feels a need to help people and civilisations in trouble. This is perfectly demonstrated in the ending where they, as Bill puts it, “jumped started a civilisation” because The Doctor removes all trace of the humans and their orders from the minds of the Vardy, essentially making them a separate and distinct race. Bill realises that life with The Doctor is about “sorting things out” even if The Doctor doesn’t always want to admit it.

Smile wasn’t a perfect episode, some of the editing towards the end was a little choppy, and the actual swarm of microbots didn’t look great. Although thanks to the overall production design, with the colony, and the spaceship having two very cool and distinct aesthetics that can be overlooked.

Finally it’s important to mention the little tease we were given at the start of the episode about the vault. Nardole confirmed that The Doctor had made an oath not to leave Earth unless it was an emergency. The Doctor clearly doesn’t want to tell Bill too much information about the vault, giving her the most vague answer to her question imaginable, “A long time ago a thing happened, as a result of the thing I made a promise, as a result of the promise I have to stay on Earth”. It doesn’t actually give us much more new information, we still are no closer to knowing what is in the vault, or who he made the promise to. But it did also open up the question, what was the thing that happened so The Doctor felt obligated to guard the vault? I can’t wait for the answers to be revealed, but that probably won’t be until the season finale.

This was another strong episode to start Season 10, there were some nice ideas, and it gave Bill a better sense of who The Doctor is as a character.