The story chronicles Melkor’s fall from grace as one of the first and most powerful Ainur created by Ilúvatar. Initially blessed with tremendous creative power, Melkor begins to desire independence from Ilúvatar’s grand design during the Great Music that creates Arda (the world). His discord in the Music becomes the seed of evil in creation.
This one’s a little different. It’s the creation myth of the Lord of the Rings (which is a really interesting mythos), but it’s told in first person via the perspective of Melkor, the creator of evil. It’s pretty long, the full video is basically the full history of that world from start to finish. I personally really enjoy the first section which recounts the creation of the spirits and thier learning how to use music to create reality.
From there it goes into how he became the evil in that world, and so on through history. I think the transition from curious to outright evil is pretty smooth. If you like a good creation myth, fun writing, and various voice actors, you’re in for a good time.
For quick reference:
Ilúvatar is God.
Melkor and his siblings are greater and lesser Angels.