Warning, warning, warning! SPOILERS TO FOLLOW.

In the global mega-hit “Black Panther,” the smartest (and most charming and endearing) person in any room she enters is Shuri, the genius teenage sister of T’Challa.

In the breakout horror film “A Quiet Place,” a girl named Regan ferociously protects her younger brother from killer creatures lurking in the dark.

In the brilliant and moving “Lean on Pete,” a teenage boy shows great resilience in the face of tragedy, and risks everything to save a horse and find himself a home.

Charlie Plummer stars in "Lean on Pete."

Charlie Plummer stars in “Lean on Pete.” | A24

One thing these films have in common: lead and/or pivotal characters who are years away from achieving official adulthood status.

Across the genres, in movies gigantic and indie-small, 2018 is shaping up as the year of the kid.

(When I say “kid,” I’m including characters up to their late teens, with an obvious acknowledgment that someone who is 18 or 19 is for all intents and purposes more adult than child. Still, if you’re being asked to save the world or at least carry a movie and your character isn’t yet 21 — that’s no small task. )

Millicent Simmonds plays a girl protecting her little brother (Noah Jupe) in "A Quiet Place."

Millicent Simmonds plays a girl protecting her little brother (Noah Jupe) in “A Quiet Place.” | PARAMOUNT PICTURES

Not all of these films have been critical and commercial successes, but I can’t remember a time when there have been so many movies with young protagonists and/or key supporting players.

Ava DuVernay’s ambitious and sometimes beautiful but ultimately disappointing “A Wrinkle in Time” featured Oprah Winfrey, Reese Witherspoon and Mindy Kaling, but the story belonged to 13-year-old Meg Murry. Reaction to the film was mixed, but young Storm Reid received widespread praise for her earnest and affecting work as Meg.

Storm Reid is Meg Murry in "A Wrinkle in Time."

Storm Reid is Meg Murry in “A Wrinkle in Time.” | DISNEY

“Love, Simon” was one of my favorite high school movies in recent years — reminiscent of John Hughes at his best. The story of a closeted teenage boy (Nick Robinson) and his three best friends (Katherine Langford, Alexandra Shipp and Jorge Lendeborg Jr.) was told almost entirely from the viewpoint of the kids. All four young actors were outstanding.

"Love, Simon" stars Jorge Lendeborg (from left), Nick Robinson, Alexandra Shipp and Katherine Langford.

“Love, Simon” stars Jorge Lendeborg (from left), Nick Robinson, Alexandra Shipp and Katherine Langford. | Twentieth Century Fox

“Pacific Rim: Uprising” introduced 15-year-old Amara (Cailee Spaeny), a plucky hacker with a lot of attitude but also a great big heart.

“Blockers” spent a lot of time on the grown-ups trying to interfere with their daughters’ prom night, but Kathryn Newton’s Julie and her high school friends were front and center in many a scene.

Gideon Adlon from left), Kathryn Newton and Geraldine Viswanathan play teenagers in "Blockers."

Gideon Adlon from left), Kathryn Newton and Geraldine Viswanathan play teenagers in “Blockers.” | . UNIVERSAL PICTURES

Even “Avengers: Infinity War” features a couple of teenage heroes. Of course there’s Tom Holland’s “Spider-Man,” who’s really still a Spider-Teen at this point, not to mention …

Groot! As you’ll recall, Groot has grown into a responsibility-avoiding teenager who can’t be bothered to spring into action — until he finally does.

Ah, teenagers.

Tom Holland as Petr Parker, aka Spider-Man, in "Avengers: Infinity Wars."

Tom Holland as Petr Parker, aka Spider-Man, in “Avengers: Infinity Wars.” | MARVEL STUDIOS

Even though the special effects are worlds apart, Steven Spielberg’s “Ready Player One” reminded me of the 1982 computer thriller “War Games” in one aspect: the dynamic between two teenagers who team up to save the world. In “War Games,” it was Matthew Broderick and Ally Sheedy; in “RPO,” it’s Tye Sheridan and Olivia Cooke.

It makes sense for the studios (and the indie filmmakers) to feature so many young heroes in so many movies. The MPAA says 18- to 24-year-olds attend more films than any other demographic — but with YouTube, Netflix, Hulu, Insta-stories, et al., the competition for attention is at an all-time high.

Olivia Cooke and Tye Sheridan play the young heroes of "Ready Player One."

Olivia Cooke and Tye Sheridan play the young heroes of “Ready Player One.” | WARNER BROS.

Granted, it’s no guarantee of box office success. Films such as “The Miracle Season” (based on the true story of a high school volleyball team that dedicated its season to a teammate who had been killed in an accident) and “Midnight Sun” (with Bella Thorne as a teenage girl coping with a rare disease that prevented her leaving the house in daylight hours) quickly disappeared from theaters.

Coming this summer: a movie that has generated nearly universal positive buzz on the festival and early screening circuit.

It’s called “Eighth Grade.”