Thor is imprisoned on the other side of the universe without his mighty hammer and finds himself in a race against time to get back to Asgard to stop Ragnarok, the destruction of his homeworld and the end of Asgardian civilization, at the hands of an all-powerful new threat, the ruthless Hela. But first he must survive a deadly gladatorial contest that pits him against his former ally and fellow Avenger...the Incredible Hulk!