Which Mythos Do You Obsess About So Hard, You Even Dream About It?

The best science fiction and fantasy universes have rich, complex backstories, including a lot of mysteries and complicated legends. And it's easy to get sucked into obsessively wondering about the rich details, and trying to answer all the questions in your head. But which mythos do you obsess about so much, you dream about it?

Please include a picture or clip or book cover that represents your mythic obsession. And please mention the name of the movie, TV show, book series, game or comic, and why you're so obsessed with it.

Top image: Simon and Marcy from Adventure Time, by Akeboshi on Deviant Art. The more we learn about the "mushroom war" and the post-apocalyptic world, and the rise of magic, the easier it becomes to obsess about.