Thor: Ragnarok Will Tie Right Into Avengers: Infinity War

Just like the Spider-Man sequel will pick up right where Avengers: Infinity War, Thor: Ragnarok will tie directly into the start of Infinity War. 

Kevin Feige, head of Marvel Studios, has long said that the original 22 movie storyline, which began back in 2008 with Iron Man, will conclude the upcoming Avengers movies.  The storyline was first hinted at in 2012 when Thanos appeared during the end credits for The Avengers, and outside of making a small appearance in Guardians of the Galaxy, Marvel has been holding on to the Mad Titan until his unleashing in Infinity War. 

In addition to the end of the story arc for the "original 22," Ragnarok will conclude the Thor trilogy.  Not only will it conclude the trilogy, but it will "drastically" change the landscape of the Marvel Cinematic Universe heading into Infinity War.  Feige, who has been out promoting the upcoming Spider-Man: Homecoming movie, had this to say about where things are heading:

“I think that we are finding ourselves as we complete Phase 3 and finish this 22-movie narrative that it’s working out that way. We did three Iron Man films, three Captain America films, three Thor films. Things change drastically in Ragnarok and then build directly into Infinity War.”

According to Screenrant.com, they've come up with a couple of things that could help Ragnarok set up Infinity War, and they are two very good points.  First, there's still one more infinity Stone that hasn't been found, and it's something that Thanos is looking for to complete his Infinity Gauntlet.  They're thinking is that since Thor has been "keenly aware" of the Infinity Stones and what their powers hold, the final Infinity Stone will play a part in Ragnarok.  The second thing that they suggest will take place deals with Doctor Strange.  Since it's already been announced that Benedict Cumberbatch's character will appear in some form in Ragnarok, and since Doctor Strange plays an important role in the battle against Thanos, it's being suggested that Thor will recruit the Sorcerer Supreme to join the Avengers in their fight against Thanos.

Which direction they decide to actually take with the movie to set up Infinity War won't be known until Thor: Ragnarok comes out on November 3, 2017.  Whatever it is, this movie looks to be a fun watch.