Chris Hemsworth is back as the mighty Asgardian Thor in the first poster for Thor: The Dark World. The actor is seen wielding his powerful hammer Mjolnir, which he will most certainly need in his battle with Malekith the Accursed (Christopher Eccleston). In addition to this one-sheet, Marvel Studios has announced that the first trailer for this Marvel Phase Two sequel will debut Tuesday, April 23, so stay tuned for that.