In the scene from Marvel Studios’ latest super-hero tale Ant-Man, in which Scott Lang (Paul Rudd) first tries out the suit that can shrink him to the size of an insect, his greatest threat is being washed down a bathtub drain, or flung from a spinning record during a dance party. During one late action sequence, Scott flees from explosions that reduce the buildings and landscape around him to rubble — except the exploding surroundings are a scale model. In his climactic battle with an equally minuscule adversary, Scott hurls a train car — one that’s a three-inch-long wooden caboose of a Thomas the Tank Engine toy.

We’ve grown so accustomed to the ever-growing apocalyptic stakes of modern blockbusters that even Scott’s mentor, scientist Hank Pym (Michael Douglas), jokes about the Avengers probably being off somewhere “dropping a city.” And that’s part of what makes Ant-Man so refreshing on a variety of levels: There’s no assumption that the stakes for a rousing adventure must include the threat of widespread annihilation. It’s a reminder that being a super-hero — aside from, you know, the occasional threat of being blown up by a supervillain — might actually be kinda fun.

The set-up finds Scott just released from a stint in San Quentin for a Robin Hoodesque burglary at a tech company, and trying to get his life back together enough to spend time with his young daughter, Cassie (Abby Ryder Fortson). But a return to a life of crime seems like the only option — until Dr. Pym shows up with that high-tech suit and a unique offer. It seems that Hank’s successor at his company, Darren Cross (Corey Stoll), is developing a similar size-reducing technology with the intent of weaponizing it. And Hank wants Scott to combine the suit’s abilities — communicating with and controlling ants, in addition to becoming the same size and strength as one — with his own breaking-and-entering talents to shut down Cross’ operation.

The planning also involves Hank’s badass daughter, Hope (Evangeline Lilly), and there’s more than enough parental and surrogate-parental angst to go around, what with Cross fuming over not getting enough approval from Hank, and Hope wondering about the mysterious, never-explained circumstances of her mother’s death, and Scott trying to convince his ex-wife Maggie (Judy Greer, wasted as per usual lately) that he should be allowed to be around Cassie. Virtually none of it works beyond the level of background noise, in part because it’s nearly impossible to make sense of Scott as a character, including the specifics of his criminal career. Rudd may be a charming actor, but it feels as though Ant-Man doesn’t really know what to do with that charm, beyond giving him a chance to flash that goofy smile a few times, and letting him be endearingly awkward when Hope is smacking him around during their training sessions.

Yet that lack of an emotional center feels less frustrating when director Peyton Reed (Down With Love) kicks the action in gear. What the story lacks in fate-of-the-universe fallout, it more than makes up for in simple pleasures, blending heist thriller slickness with special-effects-driven fisticuffs. And maybe best of all, it’s the most playful comic-book story since Sam Raimi’s Spider-Man films, from the silliness of the sequence in which Scott’s partner-in-crime Luis (Michael Peña) tries to explain how he learned about a specific break-in target, to the sheer kinetic pleasure of superhuman abilities. Gravitas gives way to what The Flash TV series is reminding us: Sometimes all you ask from costumed crime-fighters is that they leave you with a stupid grin on your face.

Because this is part of the ever-growing Marvel Cinematic Universe, Ant-Man makes sure to provide its connection to The Avengers (including an extended character cameo for one action sequence), and to set up Scott Lang’s ongoing presence in that universe. But it’s better at carving out this character’s unique place in that universe, as a hero who doesn’t necessarily need to be chasing down Infinity Stones and Tesseracts and whatnot. While Ant-Man may not have mastered giving its hero a soul, it reminds us that you can still have a blast at the movies even when the good guy and bad guy are having a life-or-death fight that can be contained inside a briefcase.