As the final installment in the Thor solo franchise, Thor: Ragnarok should tie up quite a few loose ends from the first two films. In addition, the movie is the last cosmic adventure before the Infinity War, so it will lay the groundwork for the Avengers’ confrontation with Thanos. And according to various rumors, Ragnarok might introduce the final Infinity Stone and tease the Mad Titan's motives for seeking all of the Infinity Stones.
Rumors aside, we know that Ragnarok will address Jane Foster’s absence and the fate of Sif and Warriors Three. And we won't even mention Odin’s banishment to Earth and Loki’s abandonment of the throne as Hela arrives. But how is Thor: Ragnarok going to set up the Infinity War? This could be a spoiler"¦
As the title suggests, the film could be about Asgard’s fall and the Asgardians’ demise. Keep in mind that it’s just speculation. There’s been no official confirmation, but executive producer Brad Winderbaum actually teased the end of Asgard during an interview with Comic Book.
Winderbaum said that Thor: Ragnarok took a page from Captain America: The Winter Soldier, in the sense that it will be even harder for the Avengers to fight Thanos. During Winter Soldier, the MCU was shaken to its core when it was discovered that HYDRA had infiltrated SHIELD, an event that led to SHIELD’s demise.
It’s much like how The Winter Soldier kind of took a lot of ideas off the playing field to make it harder on the Avengers in Avengers: Age of Ultron. It’s a similar thing.
In the same way that SHIELD protected Earth from threats that existed on Earth, Asgard protected Earth from threats from outer space. So what will happen if Asgard is no more? Earth will have to fight on its own or find new allies (obviously, in the Guardians of the Galaxy):
We make it much harder for those protectors to come help our heroes.
Thor: Ragnarok will hit theaters on November 3, 2017.