"It's bigger on the inside." I've heard that way too much. They seriously need to stop saying that. Doctor, calm down, you're talking to yourself again...

The Doctor has reached another planet, and it appears to be inhabited by some form of multicolored, miniature horses. It doesn't help that he seems to have become one himself. It wouldn't bother him if his first night on said planet hadn't revealed that he seemed to have already been there...