He’s tiny, now he’s big, now he’s normal-sized, he’s tiny again, now he’s REALLY REALLY BIG!

He’s … Ant-Man.

Of all the super-duper-heroes soaring through the various Movie Universes, Ant-Man is perhaps the most lightweight — not just in literal size but in terms of his gravitas as a movie character, and the scope of the adventures he undertakes.

To be sure, Paul Rudd’s Scott Lang aka Ant-Man joined Captain America and Falcon et al. in the battle against Team Stark in “Captain America: Civil War,” but in essentially stand-alone stories such as “Ant-Man and the Wasp,” he’s more likely to be matching wits with the FBI agent monitoring his parole and trying to juggle being a divorced dad with rekindling a broken romance while also doing battle with a standard-issue arms dealer than mounting a last defense against some fire-breathing intergalactic monster with the fate of the universe at stake.

Ant-Man plays small ball — and that’s that makes this sequel to the 2015 origins story such a treat. After the big-picture philosophies and the family tragedies and the dramatically heavy conclusion to “Avengers: Infinity War,” it’s nice to take a breath and enjoy a (mostly) self-contained and smile-inducing summer rollercoaster ride bolstered by the excellent comedic timing of Rudd and company, not to mention some dazzling and dizzying CGI moves designed to thrill and to score solid laughs. (Success on both counts.)

They had me at, “Get the Hot Wheels Rally Case!”

You see, when the moment calls for it, Ant-Man and/or his teammates can elude normal-sized henchmen driving normal-sized cars by shrinking their vehicles to the size of a Hot Wheels car. (Or, if the occasion calls for it, they can pick out a flashy Hot Wheels car from a case and presto! The toy car becomes a real car.)

“Ant-Man and the Wasp” follows “Captain America: Civil War” on the Marvel Universe timeline, with the main story taking place just prior to the events of “Infinity War.” (For those of you nerding out with a Marvel timeline chart.)

The eminently likable and eternally boyish Rudd (he’s 49!) is all smiles and sly quips and sheepish sincerity as ex-con Scott Lang, who is near the end of the two-year house arrest sentence he received after violating the International Superheroes Can’t Do That Act, or whatever they call it. (Of course, Scott could easily leave the ankle bracelet behind and zip around the outside world — but he doesn’t want to jeopardize his freedom and risk losing contact with his super-adorable and super-supportive daughter Cassie, winningly played by Abby Ryder Fortson.)

Our story begins as a domestic comedy/drama, with Scott sharing custody of daughter Cassie with his ex, Maggie (Judy Greer), and her guy Paxton (Bobby Cannavale), who absolutely love Scott and smother him with hugs every time they see him. (If only all shared-custody arrangements were so loving!) Meanwhile, Michael Pena’s fast-talking and quite hilarious Luis is trying to keep Scott’s private security firm afloat while Scott is under house arrest.

And then there’s the hapless but basically good-hearted FBI agent Jimmy Woo (Randall Park), who suspects Scott is up to … something, but is always a step or three behind.

Dramatically speaking, Ant-Man is a kind of supporting player in the actual sci-fi adventure, which primarily concerns the efforts by the legendary inventor Hank Pym (Michael Douglas) to reunite with his wife Janet (Michelle Pfeiffer), who was thought to be lost forever some 30 years ago when she shrank to the quantum realm — that means she got really, really, REALLY small — during a mission to stop a bomb from killing thousands of people.

Now, with the help of his daughter Hope aka the Wasp (Evangeline Lilly), Hank believes he can find Janet and bring her back — but they’re going to need Ant-Man’s help, mainly because this movie is called “Ant-Man and the Wasp,” not “Hank and the Wasp.”

(Don’t worry too much about all the “quantum realm” talk. As an utterly baffled Scott says after a particularly dense exchange between scientists, “Do you guys just put ‘quantum’ in front of everything you say?”)

Walton Goggins does his Walton Goggins thing as a slippery arms dealer with a Southern drawl who’s out to steal Hank’s lab, which occupies an entire multi-story building. (You can steal the lab because it can be shrunk to the size of a carry-on suitcase.) Hannah John-Kamen does fine work as the mysterious Ghost, who is finding it increasingly difficult to control the moments when she becomes invisible and will stop at nothing to find a “cure” for her condition. Laurence Fishburne shows up as Hank’s estranged partner in science, who is a father figure to Ghost and is torn between helping her and protecting his old friend.

Mostly, though, “Ant-Man and the Wasp” is all about the comedically energetic action sequences, and Scott and Hope getting lost in each other’s dreamy gazes, and hey isn’t it pretty cool to see Michael Douglas and Michelle Pfeiffer playing two of the best-looking badass Mature Superheroes? We’re hardly in original territory when a movie relies not once, but twice, on truth-serum humor — but even when things get ultra-corny, “Ant-Man and the Wasp” keeps merrily buzzing along.

★★★

Marvel Studios presents a film directed by Peyton Reed and written by Chris McKenna, Erik Sommers, Paul Rudd, Andrew Barrer and Gabriel Ferrari. Rated PG-13 (for some sci-fi action violence). Running time: 118 minutes. Opens Friday at local theaters.