WARNING: SPOILERS

Remember when they said you couldn’t make a successful superhero movie if you had, like, two supervillains in it? Another piece of conventional wisdom bites the dust. Along with half the Marvel universe.

To be fair, “Avengers: Infinity War” really features just one supervillain, Thanos (Josh Brolin), plus a few of his powerful minions, plus a slathering army of whatchacallms that attack Wakanda. But it also has, what, two dozen superheroes? Three dozen? Just naming them all, and the actors playing them, would take half this review.

And it works. It's fun. They did it. Yes, some characters inevitably get short shrift—see: Captain America (Chris Evans)—but I was enthralled from the get-go. “Avengers: Infinity War” is both galactic in scale and allows space for the usual Mighty Marvel petty bickering (Iron Man vs. Dr. Strange, the battle of our  cinematic Sherlocks) and spot-on humor (Ben & Jerry’s, “Rabbit,” “Wait, there’s an Ant-Man and a Spider-Man?” “Why was she up there this whole time?”). Smart people are obviously behind this, including directors Joe and Anthony Russo, writers Christopher Markus and Stephen McFeely, and Marvel impresario Kevin Feige. They’re playing the long game. DC should take notice. It should cry at everything it’s already lost.

Malthusian
The movie begins in medias res. Scratch that. It begins in media res even for those who of us who have watched the previous 18 movies in the Marvel Cinematic Universe (MCU). Now that’s some serious in media res.

Last time we saw Thor, in “Thor: Ragnarok,” the 17th of the MCU movies, he’d lost his hammer, his father, his eye, and Asgard; but he was on a spaceship, wasn’t he, with Loki (Tom Hiddleston), Bruce Banner (Mark Ruffalo) and the remnants of Asgard, heading toward Earth. OK, I guess there was some mid-credits sequence when their ship was overtaken by a bigger ship. I’d forgotten that. This movie begins with the smoldering remains of the battle that followed, while a bureaucratic voice, Ebony Maw (Tom Vaughan-Lawlor), intones how the defeated should rejoice at falling before Thanos; that it’s an honor to lose their meaningless lives in this way. It’s a good bit. Chilling. It will be repeated.

Thanos, our purple-skinned supervillain, is after the infinity stone in Loki’s possession and tortures a defeated Thor to get it—but not before Loki gets to use the line that Tony Stark used on him in the first “Avengers” movie: “We have a Hulk.” Back then we relished it because we knew what it meant. (It meant Loki being slapped around like a rag doll.) For a second, as Hulk pummels Thanos, we think it still means something ... until Ebony Maw holds back Thanos’ other minions, saying, in effect, let Thanos have his fun. And he does. He pummels Hulk into the ground. Hulk. No bigger statement could be made about the menace to come.

And this was Thanos with just one infinity stone in his possession. He soon gets the second from Loki. He’s collecting all six:

1. Power (which Thanos has at the outset)
2. Space (which he takes from Loki)
3. Mind (in Vision’s forehead)
4. Reality (with the Collector)
5. Time (in Dr. Strange’s amulet)
6. Soul (on another planet)

Apparently these stones are what’s left over from the beginning of the universe? Or something? The bigger point is they give the holder immense powers, which means that as the movie progresses, our villain, who has already pummeled Hulk, becomes even more powerful. So how do you stop him? How do the filmmakers come up with a credible rationale for defeating him in the final act (when he's a virtual god) when they couldn't in the first? That mind puzzle intrigued me throughout. 

Maybe, I thought, they don’t need to defeat him. Maybe as Thanos acquires these stones, particularly Mind and Time and Soul, he’ll become wise and abandon his plans. He’ll change. Right? How could he not? How could anyone take in the vastness of the universe and not change?

Well, he doesn’t. The filmmakers don’t go that way. The gems don’t affect him that way. I was particularly disappointed in the Soul stone, which is hidden on the planet Vormir, guarded by, whoa, of all people, the Red Skull (Hugo Weaving), and which demands that Thanos sacrifice something he loves in order to attain it. That annoyed me. Really? A sacrifice? So the Hawaiians were right after all? Worse, Thanos is standing there with Gamora (Zoe Saldana), the girl he orphaned and then raised, the daughter who hates him, and she laughs because she assumes Thanos doesn’t love anything, has nothing to sacrifice, and won’t get the stone. Which would’ve been a great twist. But no, they don’t go there, either. They go where we know they’re going. Amid tears, Thanos kills Gamora, whom he loves. She’s the last to realize this. It’s beyond telegraphed, and thus a little disappointing.

Are our heroes a little disappointing? Three of the six stones Thanos acquires in the exact same way—by torturing a sibling/compatriot of the holder:

• Thanos tortures Thor until Loki gives it to him 
• Thanos tortures Nebula (Karen Gillan) until Gamora gives it to him
• Thanos is about to kill Iron Man (Robert Downey, Jr.) so Dr. Strange (Benedict Cumberbatch) gives it to him*

* More on this later

Our heroes know the horror that awaits if Thanos gets all six stones, and yet they still give it up to save one life. What’s that “Star Trek” quote? The needs of the many outweigh the news of the few—or the one? Well, the Avengers turn it on its head. The lives of a known one outweigh the lives of unknown trillions. Including, potentially, that one. Bad math.

What is the horror that awaits? I actually like this part. Thanos figures the universe is too full, and it’s creating unending misery, so if, say, half of all life were gone in the blink of an eye, the rest of us would get along better and enjoy ourselves more. That's what he plans to do: kill half the universe. It's particularly chilling because it has its logic. Thanos isn’t some cackling, hand-rubbing bad guy. He’s a Malthusian. He thinks he’s doing the right thing, and Brolin, through motion-capture, gives him and his monstrous face and body a kind of weary dignity. He sees himself as burdened with this task. And when it’s over, he tells Dr. Strange, he’ll finally get to rest, “and watch the sun rise on a grateful universe.”

That’s some fucked-up shit right there.

Even more fucked-up? It happens. Throughout, I kept wondering how our heroes would defeat Thanos, this ever-stronger madman, because that’s how it works in the movies. The good guys win. Well, not here. Thanos wins. He gets the six stones and kills off half the universe, including Black Panther, Dr. Strange, Scarlet Witch, Falcon, Nick Fury, Spider-Man and all of the Guardians of the Galaxy—billions in worldwide box office, mind you—and then returns to, I guess, his home planet, where, on a kind of cottage in the hills, he sits down on some porch steps, sighs, and watches the sun rise.

You know the Hollywood sunset ending? The hero riding off into it? This is like that—but with the villain. Who’s just killed trillions.

That's pretty audacious. That's showing some fucking stones. 

But it leads to an obvious problem.

The obvious problem
How are they going to get all these superheroes back? It’s beyond the billions in revenue. Some of these movies are already in development with the actors attached: “Untitled Spider-Man: Homecoming” sequel with Tom Holland. And can you imagine the uproar if Chadwick Boseman doesn’t come back as Black Panther? #AvengersSoWhite.

One solution is for one of our heroes to steal the glove with all the infinity stones, then reverse everything—either through time, or, you know, just willing it. Poof. Everyone’s back. 好久不见.

There’s also the Dr. Strange factor. When Tony Stark admonishes him for giving up the Time stone to Thanos, and before he turns to dust like half the universe, Strange says, “There was no other way.” Now this could just be a self-justifying line, an idiot line to justify furthering the plot, but I don’t think so. Earlier, Dr. Strange used the Time stone to see 14 million possible outcomes to their battle with Thanos, and in only one were they victorious. So part of me thinks that’s why he did what he did: It’s the one path to victory. Apparently I’m not the only one thinking this.

“Infinity War” had its slow spots. I could’ve done with more Earth time and more Captain America. I didn’t particularly like Tony’s pause on whether to call Steve Rogers with the Earth in peril. Really, dude? You guys had a spat; get over it. And the opportunities to defeat Thanos that were lost, from Peter Quill in particular, left me shaking my head. C‘mon. Who squabbles with allies instead of banding together to fight the enemy? Besides Bernie bros, I mean.

But overall this “Avengers” is what a superhero movie should be: big, powerful, fun, and never forgetting the human equation. It even includes heartbreak. While most of our heroes simply fade and crumble silently before our eyes, Peter Parker, speaking to his mentor, Tony Stark, says these lines apparently ad-libbed by Tom Holland: “I don’t want to go. Please, I don’t want to go, Mr. Stark.” It’s heartbreaking. You realize how young he is. He wanted adventure but he didn’t want to lose everything. He had such plans. We all have such plans.