Captain America: Civil War not only single-handedly validates the “shared universe” model of storytelling but is the greatest superhero film of the modern era.

I wanted to drop the mic at the beginning so I could back up and explain why Civil War is such a monumental achievement in the history of pictures about people in tights punching one another.

In 2008, Iron Man and The Dark Knight signaled a fundamental shift in what we considered the superhero film. Each film took the genre away from the trifles of adaptation and toy-based franchising and into the legitimate, current pop cultural zeitgeist.

The Dark Knight contributed mature storytelling, the idea that heroes could engage with more than the basics of good and evil. They could engage with philosophical questions, political issues and emotional tensions.

Iron Man’s contribution was the aforementioned “shared universe” model, the idea that superheroes don’t exist in vacuums. Each had their own adventures, sure, but each affected the world in ways mentioned in other films, and eventually their stories merge. We followed our heroes and their growth across multiple, interwoven films, not just three or four that were largely disconnected.

Civil War picks up at the dangling threads of the Marvel Cinematic Universe, namely the collateral damage caused by the Avengers’ repeated attempts to save the world. After a tipping point incident in Nigeria, these tensions come to a head when the United Nations introduces the Sokovia Accords, regulations designed to put our heroes’ massive power in check and in service of the world governments.

Tony Stark (Robert Downey Jr.) supports these Accords because of his lingering guilt from Avengers: Age of Ultron, where his program was responsible for hundreds of deaths. Captain America (Chris Evans) believes it is only by their freedom to act that they have ever saved lives. This difference, combined with the reappearance of Captain America’s friend, Bucky Barnes (Sebastian Stan), leads them into a conflict that tears the Avengers apart.

Lest I make this all sound like conflict and storytelling theory, let me make something clear. Civil War is the most amazing, balls-out exciting action film I’ve seen this year. Directors Joe and Anthony Russo previously displayed an amazing propensity for action with Captain America: The Winter Soldier, and Civil War shows that simply growing their toolbox with a bigger budget and more superheroes only makes them more innovative.

Action in Civil War is visceral, pulse-pounding and next-level creative. Every blow hits with the force of a freight train, and you feel the skill and raw power that its heroes wield with every hit.

While many action movies pull that off, Civil War has superheroes at its disposal and knows how to use them. Some of the most well-thought out integrations of superhero tech and power sets ever seen on film are  in Civil War, with the culmination being a  17-minute epic fight scene at a German airport that feels like a set of comic book splash pages come to life. It’s every fantasy you ever had, back when you were clashing your superhero action figures together, come true.

But action beats that are not grounded in character motivations become weightless fluff, and Civil War has that lesson carved in its bone.

This is a film that gives every one of its characters a motivation and an arc, and makes you care about every single one of them. They all have something to learn, and they all have something to do in the film, making it amazingly compelling. At every step, you are driven forward. Some attachment, some emotion is hooked into you and takes you along for the ride.

The film has you caring about the old characters. Black Widow (Scarlett Johansson) is torn between two sides of herself and between two friends at odds with each other. Scarlet Witch (Elizabeth Olsen) is coming to grips with her powers and her place in the world. The time that we’ve spent with them in previous films is given new meaning and new depth.

You care about the new characters just as much. We’re introduced to Black Panther (Chadwick Boseman), a man thrust into power and driven by vengeance. And we’re re-introduced to Spider-Man (Tom Holland) for the third time, a young boy taken out of his small world and brought into a place that he couldn’t even imagine. They feel at home in this universe, and by the end, you’re chomping at the bit to see more.

For the first time since Loki in The Avengers, you give a damn about the antagonist. Civil War is blessed with a villain that has compelling motivations and has a plan that truly makes it seem as though he’s trying to accomplish something he believes to be good, instead of evil for evil’s sake. Helmut Zemo (Daniel Bruhl) is just a man, but he’s a man torn apart by the world the Avengers have created and driven to lash out against them.

Most importantly, you care about those who are good. Tony Stark and Captain America are two of the greatest blockbuster characters since the term was invented. They’re infinitely watchable and compelling, and Civil War adds layers to them beyond anything we’ve seen so far.

Captain America and Stark are proof of Civil War’s validation of the “shared universe” model. We’ve spent years growing with them, seeing their evolutions and their struggles and their victories. We’ve grown attached to the two characters.

And when they were pitted against each other, it legitimately got to me somewhere deep. The final act of the film is an emotional horror of a battle between Iron Man and Captain America. We see two men who want what they think is right clashing against each other in a knockdown drag-out brawl, and we just want it to stop, because seeing people who we thought were close friends fight really does hurt.

Intermingled with all of these difficult topics, there’s amazing performances, great action beats, politically smart ideas and plenty of laughs. It’s got the best superhero fight scene ever, the best Spider-Man so far and plenty of emotional bits to melt the coldest hearts. Even if you haven’t been following the Marvel Cinematic Universe, this is a great blockbuster to kick off the summer.

But if you follow the Marvel Cinematic Universe, Civil War is something more. It’s a tour de force, a culmination of all the promises made since 2008. It’s a knife to your heart, watching people you care about deeply rip each other apart and not knowing whose side to be on.

It’s a film that stands on its own and stands together with so many others. Mythology that is revitalized to feel as fresh as the first day you heard its tale.

It’s pure, raw achievement. Captain America: Civil War is the chance to watch a virtuoso play your favorite piece. There’s not a beat missed, not a note out of tune, while pulling into the deepest depths that you never knew something so familiar could have.

It’s a reminder of why I love superheroes, and why I go to the cinema.

Grade: A+