Doctor Who has always been about rebellion. It has been about the Doctor rebelling against the society in which he was born. It was always said that the Doctor stole a TARDIS and left Gallifrey because he was bored, because he staunchly disagreed with his people, the Time Lords, who held immense powers but refused to use those powers to aid others. He has repeatedly come into conflict with the Time Lords because of his chosen lifestyle; at times they’ve opposed him and actively sought to end his adventuring, and at other times they’ve taken advantage of it and used him to accomplish something that they couldn’t be seen to be involved in. In “Hell Bent”, the Doctor, after billions of years, steps out onto the surface of Gallifrey to commit his boldest act of rebellion yet. Because, you see, while this episode looks like it’s about Time Lords, and about Gallifrey coming back into the universe, and about the political fallout of the Time War, and about the fulfillment of the prophecy of the Hybrid, it really isn’t. It’s really only about one thing: a man who is losing his best friend and will take any action necessary to rescue her and keep her safe. Even if that means defying his own people. Even if that means threatening all of time and space.