The film brings together a massive ensemble cast, including Iron Man (Robert Downey Jr.), Captain America (Chris Evans), Thor (Chris Hemsworth), Black Widow (Scarlett Johansson), and the Guardians of the Galaxy, among others. The story follows the Avengers and their allies as they attempt to stop Thanos (Josh Brolin), an intergalactic mad titan, from collecting all six Infinity Stones, which would grant him unimaginable power to wipe out half of all life in the universe.