This episode was a complete surprise. The entire episode was a huge critique of the flattening of our culture thanks to social media, technology and algorithms. It was able to cleverly show how everyone in this modern society is looking losing touch with reality, only looking for like minded people and has a hard time thinking for themselves. All of this is due to a reliance on the algorithms that are in all our devices, how they (seemingly) control our actions and our interactions with the world around us. It shows how those same algorithms and our technology can turn against us as quickly as it can help us. But, I think the most telling thing of all was how all these people, despite the fact that the doctor helped them escape, refused his help in the end, because he was not one of them, or like them. All in all I would put this up against a Black Mirror episode any day. Well done, once again.a great example of what Steven Moffat can do.