“Captain Underpants: The First Epic Movie”

*

(PG, 1:39)

It’s unlikely that anyone going to a movie called “Captain Underpants: The First Epic Movie” is anticipating a strong story filled with practical real-life lessons.

That’s perfectly OK. Sometimes parents need a cinematic baby sitter. Sometimes children, especially at the end of the school year, deserve to wallow in a little potty humor. Not every family-friendly movie needs to be filled with “Inside Out”-style psychotherapy.

And yet the DreamWorks Animation film still strains to meet its modest expectations. “Captain Underpants” is a popular series that doesn’t seamlessly translate to the big screen, and the filmmakers can’t solve this problem. The result is a cinematic wedgie: a little too dark, a little too nihilistic, a little too empty.

Beyond a sadistic principal and a couple of school staff members, “Captain Underpants” is a movie devoid of adults. The better “Peanuts” TV movies handled a similar scenario by tapping into the strong friendships and carefree feelings as kids approached a holiday. Never mind if that holiday turns out to be a disaster. Humanity and fellowship win.

“Captain Underpants” presents a bleak and borderline dystopian world, where the friendship between comic book artists George and Harold (voiced by Kevin Hart and Thomas Middleditch) is the only light. Their primary joy is the short-term rush of pranking their teachers — including hypnotizing militaristic Principal Krupp into thinking he’s a superhero.

This is effective in Dav Pilkey’s “Captain Underpants” books, where the artwork suggests the slightly twisted but harmless fantasy world of a child’s mind. The comics are a small blast of subversiveness — empty calories to be consumed as the world passes by outside a car or bedroom window.

Viewed in a movie theater, “Captain Underpants: The First Epic Movie” is a more enveloping experience. The central characters are part of the cartoon, not distanced from it. As the school descends into chaos with an evil professor and homicidal toilet robots, the cynicism is inescapable.

Yet the script, from “The Muppets,” “Storks” and “Neighbors” writer Nicholas Stoller, has its moments. A whoopee cushion symphony brings Brad Bird-era “The Simpsons” to mind. Re-enactments are animated with sock puppets. As running jokes about the planet Uranus go, the ones here are strong.

But in the end it’s impossible to ignore the fact that this feature is devoid of even the simplest positive morals or takeaways. And it’s not quite funny or wry enough to forgive its weaknesses.

What’s left is a pair of XXXL briefs, a lot of toilet humor and the sense that Hollywood could do better.