‘Captain Underpants’ full of humor for all

The story centers on fourth graders Harold and George, who are best friends and the most popular pranksters at Jerome Horwitz Elementary School. When they aren’t playing tricks or being admonished by mean-spirited Principal Krupp, they’re hanging out in George’s treehouse writing comic books.

That’s where they come up with their signature superhero, the dimwitted but joyous Captain Underpants.

Imagining kooky adventures for their caped character keeps the boys creating comics and laughing for hours — sometimes in class, which draws ire from the already-angry Principal Krupp. He’s determined to catch Harold and George misbehaving, and threatens to put them in separate classrooms when he does.

In a desperate attempt to avoid punishment, the boys hypnotize Krupp and convince him he’s actually the valiant Captain Underpants.

Ed Helms voices both Krupp and the Captain, the latter with soaring optimism. Kevin Hart dials down his usual outrageousness to play George, and Thomas Middleditch of TV’s “Silicon Valley” voices Harold.

The villain here is the mysterious new science teacher, Professor P (Nick Kroll), who wants to eradicate all laughter from the school, and eventually the planet. When the students find out the “P’’ stands for Poopypants, they can’t stop laughing, and the professor is furious.

An ensuing showdown between Poopypants, Underpants, Krupp and the kids involves an army of angry, robotic toilets, because of course it does. The “Captain Underpants” books are aimed at 8- to 10-year-olds.

“Captain Underpants” connects with its key demographic through fart sounds, rogue toilets and funny names delivered in bright, saturated colors. But like the best children’s movies, it offers enough substance for ticket-buying parents, too.

Krupp, for example, lives on Curmudgeon Boulevard and keeps a sign on his school desk that reads “Hope dies here.” When Harold and George fear he’ll report their misdeeds to their parents, Krupp demurs, saying, “Your parents are obviously total failures.”

Meanwhile, Professor P is looking for a humorless mindset he can duplicate throughout the school. When he finds it in class kiss-up, Marvin (Jordan Peele), the professor says, “You have no sense of humor, like a chair or a supermodel.”

Director David Soren captures the simple drawing style of Dav Pilkey’s books but keeps the animation inventive with unexpected flourishes, including a sequence told through live-action sock puppets and another with flip-book animation “made” by George and Harold.

Creative parents’ hearts are sure to be warmed when the school arts program is reinstated, and anyone who’s ever been a kid can appreciate the fourth graders’ mission to “make school fun again.”

With its clever approach and volumes of source material, not to mention an ending (and title) that set up a possible sequel, Captain Underpants could be back, and he’d be welcome, farts and all.

“Captain Underpants: The First Epic Movie,” a Twentieth Century Fox release, is rated PG by the Motion Picture Association of America for “mild rude humor throughout.” Running time: 89 minutes. Three stars out of four.