With Avengers: Infinity War making all the money in the entire world, the nineteenth movie in a franchise that has become the pinnacle (and some would argue the nadir) of big screen popular storytelling, it’s important to look at how we got here. It all started because of one movie, 2008’s Iron Man, a movie that for many was the first step into a larger world, to steal a phrase from another franchise. May 2 marks the 10th anniversary of Iron Man, and it’s worth looking back at it as a film on its own, and also as the first piece of something that became so much greater.

The landscape of superhero movies was very different in 2008 than it is now. The early 2000s saw the beginning of the new breed of superhero movies, eschewing the camp of 1997’s Batman & Robin in favor of something slightly more realistic. This was spearheaded by the first X-Men in 2000 and the first Spider-Man in 2002, both of which had their silliness (to be sure) but were aiming for something altogether more rational.

And while there more good movies to be had–the sequels to both of those movies were excellent, as were Guillermo del Toro’s Hellboy in 2004 and Christopher Nolan’s Batman Begins in 2005–but we also had stuff that just didn’t work, like Daredevil (2003), The League of Extraordinary Gentlemen (2003), Hulk (2003), Catwoman (2004), The Punisher (2004), Man-Thing (2005), Fantastic Four (2005), and Ghost Rider (2007). Hollywood knew the comic book movie could work, but there wasn’t a ton of evidence of it working well.

So in May of 2008, with Nolan’s hotly anticipated The Dark Knight slated for July, Paramount, Marvel, and producer Kevin Feige needed to prove they had what it took. Iron Man, directed by Jon Favreau, brought something that would be the hallmark of the MCU going forward: it brought a sense of humor coupled with its badassery, and for that we had Robert Downey Jr. as the chauvinist, alcoholic genius playboy Tony Stark, who starts the movie like a Silicon Valley James Bond and through his own struggles becomes a true hero.

Famously, Downey Jr. was not a trusted name at that point, and he definitely wasn’t the highest paid actor on the set, but without his pitch-perfect performance in the central role, we wouldn’t still be talking about this movie or this franchise. The Dark Knight is excellent despite Christian Bale; Iron Man is excellent because of Robert Downey Jr.

The storyline in the movie basically follows the exact sequence of the Cambellian hero’s journey–hero starts the story one way, is forced to change through hardship, changes in the cave where he tests his mettle, returns to the world a new man on a mission, and faces demons/villains from his past before stasis is reestablished. It’s all right there, but through characterization it’s elevated. The sequences that make the movie work all have to do with Tony; first when he’s taken captive and forced by terrorists to design a bomb, then making his first suit, then the montage of him making and testing the suit, with hilarious results. They’re the must-have moments in a hero origin story, and they’re done for maximum hilarity and sympathy.

Some of the aspects in Iron Man, it should be said, flatly don’t work or feel very dated. There’s a lot of W. Bush-era politics in the opening, which now feel like a relic. The villain of Obadiah Stane (Jeff Bridges) is just a blustery corporate pirate who’s even less interesting when he becomes the Iron Monger. Little did we know this would be the mold for most of the MCU’s villains going forward. And Tony’s relationship to women–especially the not-a-character of Leslie Bibb as reporter Christine Everhart–feels laughably neanderthal even for the day.

But despite some of these downfalls, Iron Man worked, and its revolutionary after-credits scene, in which Samuel L. Jackson revealed himself as Nick Fury of S.H.I.E.L.D. and told Tony he’s taken a step into a larger world just like the audience had, gave us hope for more to come. And we’d have to wait a bit. The Incredible Hulk later that summer felt very like the underwhelming superhero movies from before; Iron Man 2 in 2010 really didn’t do it for me, despite introducing Scarlett Johansson’s Black Widow; and even though I enjoy both the first Thor and the first Captain America, they were still merely shadows of what Iron Man had been. 2012’s The Avengers made good on the promise of that first spark of the MCU.

And now, ten years later, the most recent movie in the now-ubiquitous saga has made more money than any movie in this many days ever has. Not bad for what started with a guy alone in a cave with a box of scraps.

Images: Marvel/Paramount

Kyle Anderson is the Associate Editor for Nerdist. You can find his film and TV reviews here. Follow him on Twitter!

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