Alot of details about Thor: Ragnarok were unconvered during the set visits. If you have been following the trailers and articles, we can assume that Thor's third adventure starts with him trapped in Muspelheim, a realm ruled by the fire demon Surtur, but before that thanks to producer Brad Winderbaum, we find out what the god of thunder has been up to after the events of Avengers: Age of Ultron.
"The journey he’s been on at the beginning of this movie, it’s not like five minutes after Ultron ends we start this movie: it’s a couple years later. And as we know, at the end of Ultron he’s started this quest to find the puppet master, and the Infinity Stones, and all that. What he realized really fast– I don’t think I’m giving too much away because it’s right at the top of the film, but basically that one quest, that universe-ending peril that he was trying to figure out dovetailed or branched off into any number of universe ending-perils that he’s been adventuring on for the two years leading up to the beginning of this film", explains Winderbaum.
We will have to wait less than 2 months for the more details as Thor: Ragnarok opens up in theaters November 3rd, 2017
Avengers: Infinity War opens up May 4th, 2018