The gang’s all here, and they’re not particularly happy. (Marvel Studios)

It all started in 2008 with a film about a genius billionaire playboy philanthropist. We’ve been through the good (“Doctor Strange”), the bad (“Thor: The Dark World”), the great (“Captain America: The Winter Soldier”) and the sublime (“Black Panther”). After 18 movies about the Avengers or Avengers-to-be, we’ve arrived at “Avengers: Infinity War,” a film that contains some number of those characters that I’m not going to say because that would be saying too much.

Plots have varied, but the one consistent thing in the Marvel Cinematic Universe movies has been the characters (well, that and my deep, abiding distaste for Pepper Potts). Gods and assassins, men of science and women of combat — the only thing that linked them was the desire to do something right and to right something wrong.

Now they get to do it together.

The plot of “Infinity War” is easy enough to discuss without spoilers: There is a bad guy, Thanos. He wants to do a bad thing to the universe using the Infinity Stones, which give him powers and stuff.

Coming in at a long but necessary 2 hours and 36 minutes — so pee first and lay off the Coke — “Infinity War” is primarily about getting the gang together. Directors Anthony and Joe Russo, the team behind “Winter Soldier” and “Captain America: Civil War,” have largely managed to do it well. They’ve teamed up the right characters so the disparate tones of their solo movies start to seep into one another.

The Russo brothers have a heavy burden to contend with: a crazy number of characters and an almost-as-crazy number of storylines. They carry the unwieldy tangle relatively well; “Infinity War” is nicely paced, with some well-placed gasps and the best surprise entrances of any Avengers movie so far. Still, there is a lot going on, plotwise, so they took the best approach possible: They rely on their characters.

The directors took a story largely unrelatable on a personal level — few of us have fought a giant purple guy — and framed it through the eyes of largely relatable people, most of whom we already knew. It’s less a story about what, and more of a story about who. And who is almost always better.

The best moments are the small, character-focused ones. What other movie could make me feel so proud of a kid from Queens, so humbled by a Norse god, and so inspired by a video-game-obsessed teenage tree … thing. Add in the fact that rumors of a major death or deaths have been swirling for at least a year and I was basically worried about everyone the entire time.

We’ve been through so much, these characters and their audiences. We might like them at different levels — we might not like them at all, PEPPER — but we’ve stuck together. We’ve lived a lifetime through good and bad, laughs and grief. And though we’re not finished, “Infinity War” feels like we’ve reached some kind of ending. Above all, it’s given audiences a chance to look over a landscape populated with every kind of person we can imagine and realize that somehow we’ve become family.

3 characters we’d kill to see flying solo
Eight of the heroes in “Avengers: Infinity War” have had their own movie — nine if you count those scoundrels from “Guardians of the Galaxy.” Here are three supporting characters in the Marvel Cinematic Universe who deserve a film of their own.

Loki
A Loki movie wouldn’t even need a plot — it could be a series of vignettes where the morally ambiguous brother of Thor just hops from dimension to dimension playing practical jokes and charming his way out trouble. And, of course, trying to take over the universe. He tries that a lot.

Bucky
Like his best friend Steve Rogers, Bucky Barnes was cryogenically frozen; unfortunately for him, he was iced by bad guys, which eventually led to his brainwashing and becoming the Winter Soldier. Let’s see what happened in those probably-not-happy torture days.

Shuri
Black Panther’s little sister equips him with stuff so important that he’d basically be dead without it. Give the genius inventor/princess a movie where she builds awesome things and uses them awesomely while constantly annoying her big brother.

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