Thor: Ragnarok official synopsis reveals the nature of Thor and Hulk's relationship

Despite knowing that a third Thor movie was coming for years - and knowing Hulk would be involved in some way for nearly as long - we don't actually know that much about the Thor: Ragnarok plot. Bits and pieces have popped up, sure, but we didn't know how they fit together until today, when Marvel released an official synopsis for the movie. And here it is:

"In Marvel Studios’ ‘Thor: Ragnarok’, 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 gladiatorial contest that pits him against his former ally and fellow Avenger — the Incredible Hulk!"

We'd heard that Ragnarok would incorporate pieces of the Planet Hulk storyline since last spring, but this synopsis confirms how. My guess is this gladiator's battle will be quite early on, and we'll spend the majority of the film with Thor and Hulk palling around the realms - Mark Ruffalo said in October 2015 that the movie would be a "buddy picture," after all.