In the Norse mythological tradition, the term Ragnarök refers to a great series of cataclysmic events through which the slate of Earth may be struck completely, wiped clean, and started anew. It’s like a slightly more optimistic version of the apocalypse, wherein two survivors will begin again in a purer, kinder world. So when Marvel revealed that the third installment in Thor’s solo series of films would be titled Thor: Ragnarok, everyone knew what was up. This is not Thor: Day at the Beach or Thor: Light Picnic. In the parlance of “the streets,” it’s going down.