(CNN) Receiving a power boost from the Marvel stable, "Men in Black: International" returns to the goofy universe where the wackiest tabloids contain the real news and aliens hide in plain sight. The movie conjures some of the goofy charms associated with the franchise, but sags in its midsection like "Endgame"-vintage Thor before nicely rallying at the finish.

All told, it's a breezy but too-often flat popcorn movie, one that tests the considerable chemistry of its stars, former "Thor" compatriots Chris Hemsworth and Tessa Thompson. That the movie holds up as well as it does is a tribute to the two, but it's more a case of occasional sparks than catching lightning in a bottle.

It's been 22 years since the comics made the jump to the screen, and despite the "International" designation, director F. Gary Gray ("Straight Outta Compton") goes back to a familiar formula, with a new agent, M (Thompson), getting on-the-job training from Hemsworth's battle-tested H, whose former partner High T (Liam Neeson) now oversees the London bureau.

The dynamic, slightly tweaked from the first "Men," is that H has become a rather hard-partying screw-up, marring his once-gilded rep, while M has grown up longing to be part of an organization she learned about as a kid, having prepped her whole life for the opportunity.

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