They bring the action and the charm, but who makes the franchise — the stars or the characters?

“Avengers: Infinity War” boasts so many stars — Robert Downey Jr., Scarlett Johansson, Chadwick Boseman, Groot! — that even with the color-coded cork board I’ve set up in the office, I can’t keep track of the dozens and dozens of name-brand actors and characters appearing in part one of Marvel’s curtain-closer saga.

Meanwhile, “Incredibles 2,” the summer’s other highly anticipated superhero movie, is animated, which, of course, means there are no stars. The characters are the film’s biggest selling point, not to mention the fact that writer-director Brad Bird is making, finally, the one Pixar sequel that everyone has been waiting to see. (Sorry, Dory.)

Do stars even matter to summer tent-pole movies any more? To put it another way: Would you still see the latest “Jurassic Park” movie if it starred, say, Milo Ventimiglia instead of Chris Pratt?

Or perhaps even more to the point: Do you even know the name of the actor playing Han Solo in the standalone “Solo: A Star Wars Story”? (It’s Alden Ehrenreich, so I’m guessing no.)

Let’s be clear: Movie stars aren’t completely superfluous to some would-be summer blockbusters. No one would care about “Skyscraper” if Dwayne Johnson wasn’t headlining it. Johnson has become so amazing in the eyes of audiences that even the most extraordinary obstacles — terrorists, gravity, a fire in the world’s tallest building — still seem insufficient because … he’s the Rock. So the writers had to give his character a prosthetic leg to even out the odds. (Still … he’s the Rock.)

Which is probably why Tom Cruise is jumping out of an airplane at 25,000 feet for “Mission Impossible — Fallout,” the latest entry in a consistent, star-driven franchise and, seemingly, the best Cruise can do these days since taking another famous leap (the one off Oprah’s couch) 13 years ago. Though he turned 55 last year (he’s born on the third of July), Cruise appears determined to hold on to the label of “ageless” for as long as possible. His next movie: “Top Gun: Maverick.”

The “Mission Impossible” movies go back 22 years, but it might as well be a 100 given how radically the film business has changed. Netflix and Amazon have ascended. Streaming has replaced physical media. Global box office fully drives decision-making. (“Rampage,” another noisy, Johnson-topped extravaganza, has grossed 75% of its take overseas. Same with Steven Spielberg’s dopey, dystopian “Ready Player One.”)

A few months after Cruise embarked on that inaugural “Mission,” moviegoers could see him in “Jerry Maguire,” the kind of mid-budget (Cameron Crowe’s movie cost about $50 million, which, adjusted for inflation would be about $80 million today) movie for grown-ups that studios no longer produce.

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So even if Johnson wanted to venture from his action-adventure sandbox into something a bit more character-driven, something a little less fast and furious, his options are limited because Hollywood just isn’t making many movies these days that don’t allow for sequels, merchandising and expanded Cinematic Universes.

But given the opportunity, Johnson could be charming. (For proof, look no further than his exuberant comic vocal turn in “Moana.”) And on the occasions Pratt has been allowed to act opposite flesh-and-blood humans and not CGI dinosaurs and raccoons, he has held his own — even against the likes of Denzel Washington, who, by the way, has a movie coming out this summer (“Equalizer 2”) that would be of no interest if he wasn’t the star.

Nor would anyone care about “Oceans 8,” the all-female spinoff of Steven Soderbergh’s three “Oceans” movies, without its stellar all-female cast. Soderbergh’s trilogy was an exercise of style and star power with the likes of George Clooney, Brad Pitt, Matt Damon and Don Cheadle gliding through capers that were seamless and, truth be told, a tad cynical. Three of these movies was about two too many.

Like “Skyscraper” and “Mission Impossible,” “Ocean’s 8” is an aspiring summer blockbuster dependent upon the good will its cast has banked with moviegoers. (It’s directed by Gary Ross, whose résumé — “The Hunger Games,” “Seabiscuit,” “Pleasantville” — seems at odds with the breezy tone of the franchise’s history, which includes the 1960 Rat Pack film.) An ensemble featuring Sandra Bullock, Cate Blanchett, Rihanna, Sarah Paulson, Mindy Kaling and up-and-comer Awkwafina would seem to have something for everyone, provided your enjoyment of movies isn’t entirely based on the predominant presence of XY chromosomes.

But if you are one of those people, don’t despair. (Or do, but for reasons best explained by a licensed therapist.) “Deadpool 2” will be arriving this summer too, thirsty to please its adolescent-minded male audience with its exhaustive (and exhausting) brand of smug lewdness.

The “Deadpool” movies would probably be just as successful if they starred Jake Gyllenhaal instead of Ryan Reynolds, though Reynolds sports a writing credit on the sequel, so maybe he’s in touch with his inner troll to such a degree that no one else could play the part.

And if that’s the case, good on him. Because in these days of franchises, stars have to go above and beyond to avoid extinction. Because the thing about cinematic universes, they contain black holes too.

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glenn.whipp@latimes.com