I often complain when a sci fi/action blockbuster has a story that could explode into a humongous finale, but instead settles for a low-stakes third act in which hero battles villain mano-a-mano in an isolated locale – see Men in Black or even Iron Man. But after the exhausting third acts of Marvel's Guardians of the Galaxy and Avengers: Age of Ultron, with their jillions of CG spaceships and robots, it's actually a relief that Ant-Man eschews the planet-in-peril bombast and is content to keep its scope, well, minuscule.

More of a heist movie than a superhero film, Ant-Man concerns altruistic thief Scott Lang (Paul Rudd, likable if out of his depth), who is freshly released from prison and trying to rebuild his life when retired inventor Hank Pym (Michael Douglas) enlists him to don his secret shrinking/growing Ant-Man suit, and stop an evil corporate usurper (Corey Stoll) who's trying to perfect his own suit, known as the Yellowjacket. It's one of many nods to the complicated comic book backstory, here tweaked to include Pym's late wife (a.k.a. Wasp) and a brilliant and beautiful daughter (Evangeline Lilly) who is Lang's age and – well, you can guess where that one's headed.

With its corporate one-upmanship and its hi-tech power-suits, Ant-Man owes a lot to Iron Man. If it was released any earlier, it would have seemed like a retread. But in the middle of Marvel's mind-numbingly ambitious five-year-plan, with cross-film storylines building up to an all-out intergalactic war in the next Avengers installments, Ant-Man is refreshingly light summer fare. Ideal for families and popcorn.

That said, it's well-known that original director Edgar Wright was fired from the production (he and partner Joe Cornish retain story and screenplay credit), so film geeks must surely wonder how Wright's Ant-Man would have differed. Was he reluctant to bow down to Marvel head honcho Kevin Feige's demands to shoehorn various Avengers references into the plot? Did he turn up his nose at the studio's insistence on a draggy, exposition-filled first act? Or was his approach just too hyperkinetic and goofy for the Marvel brand? As of now, no one will say, though it's hard to resist guessing what aspects of the film are true to Wright's vision. (Some witty montages bear his signature.) In any event, I don't envy Peyton Reed, a middling but not untalented comedy director. Fanboys are dismissing him as a studio hack, but what if his Ant-Man is better than anything Wright would have made?

Anyway, it's a good time at the movies. It's predictable but fun. Michael Peña provides welcome comic relief, Michael Douglas is committed and appealing, there are clever moments throughout the film, and I liked the score by the incredibly prolific composer Christophe Beck.