This episode is mostly a big story of Edda in her young days, when she met Raine Whispers. I think it was fantastic. We got to see glimpses of the younghood of relevant characters. And at the end of the episode we see a few ways of the past affecting the present.
But of course the most important part was the fun Edda and Raine lived together. We can feel their fast friendship and we begin to understand why what is currently happening with Raine affects Edda so much. And it makes us root for those two even more. I like the way this show manages its backstories. If you like that, this episode is for you.