One of the main reasons for the longevity of the Marvel Cinematic Universe – aside from the fact that the moviegoing public really, really likes superheroes right now – has been its riveting character arcs. At a certain point, the comic book spectacle stopped being the MCU’s primary draw, and audiences were instead coming to see where these characters would be taken next.

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Fans were just as interested in Tony Stark as they were in Iron Man and 'The Infinity Saga' took Tony on an emotional rollercoaster over the years. if you want to know more here are the 9 MCU movies you need to watch to follow Iron Man's character arc.

Iron Man

Tony holding up his laser arm in Iron Man

The movie that started the MCU is also the one that started Iron Man’s character arc. Tony Stark grows a lot as a person over the course of his first solo outing. When we first meet him, he’s a billionaire playboy who turns a blind eye to the fact that he’s profiting from the War on Terror. It takes getting captured by Stark-powered terrorists in Afghanistan to finally turn his life around.

Instead of building the bomb that they want him to build, he creates a metal suit that will allow him to burst out of the cave, blowing up his captors along the way. Upon returning to the U.S., he improves the suit and becomes a superhero, announcing to a room full of reporters, “I am Iron Man.”

Iron Man 2

Tony Stark eating a donut in his armor in Iron Man 2

In Iron Man’s next movie, Tony was being continually pestered by S.H.I.E.L.D. about joining the “Avengers Initiative,” while his alcoholism was creating problems for his relationship with Pepper and the arc reactor in his chest was turning his blood toxic.

The U.S. government was imploring Tony to give them the Iron Man technology, since they and other countries’ governments were trying and failing to emulate it. Tony refused, because he was pleased to have privatized world peace. By the end of the movie, Tony managed to get his groove back by being inspired to invent a new element by an old video of his dad where he called Tony his greatest creation.

The Avengers

Iron Man carrying nuke into space

Despite not playing well with others, the coming of Loki and the threat of an alien invasion forced Tony to finally join the Avengers. He became best friends with fellow scientist Bruce Banner and butted heads with Steve Rogers before the team came together to fight in the Battle of New York.

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Although Earth’s mightiest heroes were doing a fine job of holding off Loki’s alien army, the Chitauri, the world government didn’t think they’d manage it and decided to write off Manhattan and just send a nuke there. Thinking fast, Tony grabbed the nuke out of the sky and flew it through the wormhole, destroying the mothership and deactivating the alien soldiers. Then, they went to get shawarma.

Iron Man 3

In his third and final solo outing, Tony Stark was suffering from serious PTSD attacks in the wake of his near-death experience in the Battle of New York. He was compulsively designing new suits, because he feared that each one wouldn’t be good enough to keep him safe. And then, a terrorist blew up his mansion and J.A.R.V.I.S. flew him into the night until he ran out of juice in Tennessee.

Struggling to power up the one suit that he had, Tony had to face his terrorist foe alone, without the use of his technology. It really put Tony’s wits and heroism to the test, even if the Mandarin reveal was a bitter let-down.

Avengers: Age of Ultron

Iron Man's vision of the dead Avengers

Tony Stark played God in Age of Ultron. After Scarlet Witch induced a vision in which he saw his worst fears realized – a cosmic threat arriving that killed all his friends, that he couldn’t stop – Tony decided to secretly use the Mind Stone to create an artificial intelligence that would act as “a suit of armor around the world.”

In true Frankenstein fashion, that A.I. became sentient, deemed humanity unworthy of protection, and set about wiping them out. Suffice to say, the other Avengers were not impressed, but by pooling their skills together, Earth’s mightiest heroes prevailed and defeated Ultron.

Captain America: Civil War

Traditionally, roguish lone wolf Tony Stark would be the one to reject the Sokovia Accords, while star-spangled goody-two-shoes Steve Rogers would be the one to sign up. But in the context of the MCU, it made sense that Tony would sign the Accords and Steve would refuse to.

Tony had to look into the eyes of a mother whose son’s death was his fault but Steve had just been betrayed by the government. This led to the Avengers being irreparably torn apart.

Tony recruited Peter Parker, who would become his surrogate son. The fight at the airport in Berlin wasn’t too brutal, but the fight over Bucky certainly was. Tony genuinely thought that Cap was going to kill him, and took his shield back.

Spider-Man: Homecoming

Tony Stark confronting Peter Parker on the ferry in Spider-Man: Homecoming

Obviously, Spider-Man: Homecoming is Spider-Man’s movie, not Iron Man’s, but Iron Man is featured heavily. Peter Parker spends the whole movie trying to get Tony Stark’s attention as he chases down the Vulture and his arms dealing ring against Tony’s wishes.

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This movie has the clearest look at Tony and Peter’s father-son bond in the MCU, from their awkward hug in the car (“We’re not there yet”) to Tony’s tough love taking the suit back (“If you’re nothing without the suit, then you shouldn’t have it”) to Peter ultimately making Tony proud and being offered a spot on the Avengers, which he turns down.

Avengers: Infinity War

Avengers Infinity War Ending - Iron Man

For six years, we watched Tony fret over the arrival of Thanos. He feared that a villain he couldn’t defeat would eventually rear his head, and in Avengers: Infinity War, he did.

Thanos planned to collect all six Infinity Stones, snap his fingers, and wipe out half of all life in the universe, and with virtually no effort, that’s exactly what he did.

Tony’s most advanced suit was no match for Thanos, who stabbed him through the abdomen and said, “You have my respect, Stark.” Peter turned to dust in Tony’s arms and he was left stranded on an alien planet, with the knowledge that he failed.

Avengers: Endgame

Avengers Endgame Trailer - Iron Man Helmet

Tony Stark got closure in every sense of the word in Avengers: Endgame. Five years after his worst fears came to fruition, he’d moved out to a cabin in the woods for a tranquil life with Pepper and their daughter named Morgan.

Then, the Avengers came knocking and asked him to figure out time travel. Unable to rest knowing that he could save Peter and trillions of others, Tony reluctantly agreed to help, and with that, let go of the resentment he felt towards Cap.

Along the way, he got to have one final conversation with his dad. And then, in the final battle with Thanos, he grabbed the Infinity Stones and did a finger-snap of his own to wipe out the Mad Titan and his armies, which killed him. Pepper summed it up best at his side: “You can rest now.”

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