This one was too close to call since the soundtrack actually plays an integral part to each movie. So I’m counting them both together, and if the third one was already out at the time of writing I’m sure I would have included it as well.
Guardians of the Galaxy kind of came out of left field for a lot of people. Compared to other giants in the Marvel universe, the Guardians didn’t get nearly as much attention, especially in a post-Avengers (2012) world. But with James Gunn at the director’s helm and lots of free reign, a new story was given to us that just brings a certain amount of levity that we might not have known that we needed. And as I said, the music plays a part in each film. Peter Quill, our rogue hero known as Star-Lord, takes with him mixtapes made by his late mother everywhere he goes, even risking his life for them at times. While that may seem a bit childish at first, it was one of the only things he had of hers before he went to space, and they helped him get through many rough patches in his life. James Gunn took a long time to make sure that when these songs played they helped tell the story or develop the characters past what the script alone could do.
(There’s also the fact that the titles of these mixtapes are pretty much exactly how I named mix CDs back in the day!)
Marshall's Matters 