A CinemaCon attendee on Monday in Las Vegas. (Chris Pizzello/Invision/AP)

Filmgoers plotting their upcoming weekends can plan on seeing “Pet Sematary,” “Avengers: Endgame” and other major studio releases.

The months beyond? That will depend on an unusual hybrid convention about to unfold at a Las Vegas casino.

The gathering is known as CinemaCon, and it takes place annually in April. Hosted by the Washington-based National Association of Theatre Owners (NATO), it helps shape the overall experience of multiplexes and determines the films playing at them.

Owners of the nation’s approximately 40,000 movie screens — executives from giants such as AMC and Regal but also operators of boutique and regional chains — will attend.

So will an abundance of stars and studio executives, who come to pitch their offerings to those theater executives, known as exhibitors, getting them amped to book and push their movies through 2019 and beyond. The convention primarily runs from Tuesday through Thursday.

“2019’s slate is incredibly promising, thanks to titles with characters that audiences love as well as original stories from exciting directors,” NATO chief John Fithian told CinemaCon attendees at a keynote address Tuesday morning. “People are ready to go to the movies a lot in 2019.”

Domestic box office was up 9 percent in 2018, the most in nearly a decade. But the gains came largely because of superhero movies such as “Black Panther,” “Avengers: Infinity War” and “Incredibles 2” as consumers abandoned their couch and its streaming options primarily to see big franchise films.

The box office in 2019 has been a more tepid affair, with revenue down 22 percent by the last weekend of February. The numbers have since picked up with the release of “Captain Marvel” and Jordan Peele’s “Us” but are still well off 2018’s pace.

This year’s presenters will try to change that, riding the franchise wave while seeking to break out new hits.

It’s in Caesars Palace’s Colosseum theater — a 4,000-seat, well, colossus — where much of the action takes place. A given studio will take over the room for several hours and show clips and parade personalities in front of the theatrical tastemakers (and, yes, plenty of media).

Executives come to talk about their overall strategies; stars take the stage to disarm and bring a touch of glamour.

While actual business can be nebulous — many of these movies are already booked throughout the country — how a film goes over with theater owners can play a role in the number of screens it lands and, indirectly, the length of its run.

Among the many dozens of appearances last year were several standouts. Paramount Pictures had a segment in which Tom Cruise and director Christopher McQuarrie talked about the real-life stunts Cruise performed for the summer release “Mission: Impossible - Fallout” in ways that captivated even normally stoic attendees.

And Universal Pictures’ presentation featured a surprise performance from Cher, complete with bedazzled dancers, that wowed the room and set the stage for the release of “Mamma Mia! Here We Go Again.”

The moments paid off. Both films went on to become hits, with “Fallout” grossing nearly $800 million worldwide.

But not all strong presentations translate into dollars. Tiffany Haddish and Kevin Hart made a well-received appearance on behalf of their two-hander comedy “Night School” last year, as did Kate McKinnon and Mila Kunis for their action comedy “The Spy Who Dumped Me.” But neither film was able to generate much business at the box office.

The convention can also set the tone for the media.

Coming into the 2018 CinemaCon, Bradley Cooper’s “A Star Is Born” was beset by questions after a revolving door of directors and skepticism about whether Lady Gaga could make the transition from singing to a lead acting role. But new footage dazzled the room, which quickly bought into Cooper’s CinemaCon pronouncement that Gaga was “a revelation.” The movie went on to become one of the biggest hits of the year, grossing $215 million at the U.S. box office.

Other 2018 stand-alone smashes also began their run at CinemaCon. Fox showcased some of the first footage of Rami Malek in the Freddie Mercury biopic “Bohemian Rhapsody.” The material was well received, and the movie went on to gross $216 million and net Malek a best-acting Oscar.

On Tuesday, Warner Bros. will attempt to replicate its “Star” feat when it presents its upcoming films. Expect pushes from its new “Joker” movie, the latest installment in its “Godzilla” franchise and the adaptation of the literary sensation “The Goldfinch.”

Universal, Disney and Paramount will follow in the coming days. Fox will not have its own presentation, with its offerings rolled into the session of recent acquirer Disney.

Smaller studios such as STX and Lionsgate will also present. Sony has opted not to present this year.

Among the 2019 films likely to get the star and spotlight treatment — and offer tea leaves about their quality and fate — are a new film adaptation of the Sonic the Hedgehog video-game character (Paramount), a live-action “Aladdin” starring Will Smith (Disney), and a splashy cinematic take on “Cats” featuring Taylor Swift and Jennifer Hudson (Universal).

Meanwhile, some companies will look to capitalize on buzz begun at January’s Sundance Film Festival, particularly the high-spending Amazon Studios, which will screen its Mindy Kaling-Emma Thompson acquisition “Late Night” in an attempt to stir buzz on the order of its Sundance breakout “The Big Sick” several years ago. (Amazon’s chief executive, Jeffrey P. Bezos, owns The Washington Post.)

The convention is also a venue for theater owners to hash out future innovations. It was the place, for instance, where recliner seats and their relative costs and benefits began to be discussed in earnest a number of years ago. At this year’s event, there will be a presentation on new solar options as well as a host of in-theater entertainment options, such as a NASCAR race simulator that will allow networked play across theaters and an app-based competitive trivia game called Noovie Shuffle that will soon launch.

Theater owners at the event will also tackle questions such as “How Is the Evolving Conventional Concession Menu Affecting the Overall Profitability of the Cinema?” At a panel with that title, a University of Memphis scholar will present findings on whether upscale food options will cut into sales of high-margin items such as popcorn and soda, with concrete implications for snack offerings in theaters.

What happens in Vegas, in other words, will soon be happening in theaters across the country.