“PACIFIC RIM UPRISING”

*** 1/2

(PG-13, 1:51)

At the end of the monsters-versus-robots flick “Pacific Rim,” a breach at the bottom of the Pacific Ocean is closed, plugging a hole that allowed hellish creatures to emerge and terrorize the globe. But after the movie earned $400 million worldwide, was that portal really going to stay closed?

No, of course not. And, with sincere apologies to the front-line cities on the Pacific Rim facing a mauling, we say thank goodness, because the new sequel “Pacific Rim Uprising” is a visually-stunning, expertly crafted dose of cheer-at-the-screen fun. It’s the definition of what a blockbuster sequel should be.

“Pacific Rim Uprising ” uses a lighter palette and is geared toward a younger audience than its 2013 predecessor, but it keeps all the key elements, upping the special effects and finding honest moments and humor in the midst of world-destroying carnage. It satisfies on every front.

Success wasn’t foreordained for the sequel. Original writer Travis Beacham and director-writer Guillermo del Toro haven’t returned (though del Toro is still a producer), nor have its original stars, Charlie Hunnam and Idris Elba. (Elba had a very good reason for not showing up: He blew himself up in the final moments of the original to keep the Pacific portal closed.)

Steven S. DeKnight, who created and ran the TV series “Spartacus” on Starz, was tapped to direct while del Toro focused on the smaller monster movie “Shape of Water.” DeKnight also teamed up with Emily Carmichael, Kira Snyder and T.S. Nowlin to craft the new story, which champions outsiders and misfits as well as celebrates makeshift families and teamwork. Plus, some stuff gets pummeled.

First, a step back for anyone not familiar with this horrific near-future: Aliens have sent giant monsters called Kaiju to soften us humans up ahead of world domination. But we’ve created 270-foot tall robots called Jaegers to fight back. They’re so big they need to be manned by pairs of operators who build a neural bridge between their minds so they can work together.

The new film opens in 2035, 10 years after the last Kaiju was defeated and the breach closed. It’s the calm before the storm. Our heroes now are Jake (John Boyega), the rebellious son of Elba’s character, and the teen orphan Amara (Cailee Spaeny), who builds her own Jaeger out of spare parts. They join together to help the military fight a new opponent — a rogue Jaeger that comes out of the sea and stomps around menacingly. It is soon clear there’s a conspiracy afoot.

Boyega, fresh off his “Star Wars” gig, is great here, as a dashing rogue who struggles under his father’s shadow but soon earns the respect of his peers. “We are a family now and we are Earth’s last defense,” he says. He and Spaeny have an easy rapport and some moments between them seem genuinely charming and goofy.

Charlie Day and Burn Gorman reprise their roles as squabbling scientists, and Rinko Kikuchi is back as the adopted daughter of Elba’s character. The rest of the cast is multiethnic, competent and very sweaty. The robots now have hologram interiors and the monsters seem less homages to past movie Kaijus and more designed to permanently upset our dreams.

If the first movie’s fight sequences were often set in the rainy dark, “Pacific Rim Uprising” embraces the light. Cities are flattened during the day as monsters and robots slug it out. Skyscrapers get punched, debris cascades down and cars get swiped around. The connection between special effects and human actors is seamless and astonishing. The level of detail — from complex cityscapes like Shanghai and Tokyo to the icescapes of Siberia — is brilliant.

The filmmakers have abandoned del Toro’s political touches — pollution as a factor in the creature attacks and building a wall to stop them, for example — but wisely adopted his sly humor. In one loud fight sequence, massive monsters and robots trade punches and one buckles, pancakes on the street and skids to a thudding, thundering stop, only slightly nudging a parked cherry red subcompact in the process. The little car’s alarm soon wails indignantly. Those little touches — Muzak played in a tense elevator during an invasion or a battle beside a museum’s dinosaur exhibit — leaven the violence.

Part of the success of the “Pacific Rim” films is that they have cobbled together enough elements of other films to make them familiar yet newish. They owe “Blade Runner,” ”Independence Day,” ”Minority Report,” ”Star Wars” and, of course, “Transformers” — not to mention every Godzilla movie ever made — some residuals. But they also have defined and introduced their own world and language.

It may not be nuanced, but it taps into something mythical — ferocious monsters rising from nowhere to be battled by 21st century swordfighters. And it’s exhilarating, like when one triumphant Jaeger gazes down at a downed opponent after a climactic fight and insouciantly lifts its middle fingers. “Pacific Rim Uprising” is so confident in itself that it basically promises a third film as the end credits roll. We can’t wait.