For some odd reason, people really like The Angry Birds. The video game has been downloaded over three billion – yes, billion – times and is one of the most popular mobile apps ever. Why? I have no idea.

In the game, you launch birds at green pigs with a slingshot. That’s it, at least as far as I know; I only played it twice. The video game’s lack of narrative however, could make for a great movie adaptation. With such a tenuous premise, the game provides unlimited creative freedom for a screenwriter. That’s why I thought The Angry Birds Movie could have been pretty good. As it turns out, it’s just okay.

Written by The Simpsons and King of the Hill writer Jon Vitti and directed by Clay Kaytis and Fergal Reilly, The Angry Birds Movie attempts to sketch an story out of a lonely outcast with heroic ambitions. What results is something largely humorless, flat, and forgettable. Red, voiced by Jason Sudeikis, is an angry bird, and is ostracized by his community on Bird Island. Reprimanded for his temper, Red is sent to anger management class so he can become calm and carefree like his feathered neighbors. There he meets Josh Gad’s jittery Chuck, who’s like Frozen’s Olaf on uppers, Danny McBride’s Bomb, who impulsively explodes, and Terence, a groaning angry bird voiced by with noises made by Sean Penn. While Red learns to stifle his anger through yoga, meditation, and group therapy, his most criticized characteristic becomes what’s needed to save Bird Island.

This is when The Angry Birds Movie attempts to pull an Inside Out, and show how seemingly unwelcome emotions like anger can ultimately be good things. When Red tries to warn the birds about a suspicious gang of green pigs who arrive on Bird Island, he’s ignored. But once the pigs, led by Bill Hader’s Leonard, trick the birds and steal their eggs, the island turns to Red for guidance. By encouraging the birds to embrace their anger and fight back, The Angry Birds Movie tries to inject the kid-friendly message that sometimes it’s okay to be angry.

But it doesn’t totally work. Sure, the birds get angry and take turns launching themselves into the pig’s city via slingshots. Slowly, though, the movie becomes more focused on the action sequences in the birds vs. pigs showdown and less interested in developing characters into anything beyond cute faces with familiar voices. In between, it indulges in silly visual moments, like when one bird shoots fireballs out of her butt, sans explanation, or when Chuck takes down pig guards à la Quicksilver’s kitchen sequence in X-Men: Days of Future Past. There’s also a Shining reference to give parents something to laugh at.

The only problem is, the movie isn’t very funny. I saw it in a theater full of young children and parents and I heard more laughs from the adults. Filled with nods to modern cultural fads, the movie’s dialogue is littered with minor jokes about yoga positions (birds doing Downward Dog, ha-ha), “fro-yo,” gluten-free cakes, and “spoiler alerts.” While humor directed at adults can often be a clever parts of children’s movies, these felt lazy. Give me bird puns all day, but please, don’t give me birds with selfie sticks.

With uninteresting dialogue (and almost none for Penn and Kate McKinnon), the movie fails to take advantage of its well-known and comedic cast of voices. Peter Dinklage as the revered mythical Mighty Eagle is the biggest disappointment (with Tony Hale’s small cameo as a flamboyant mime bird who pops up a few times only to utter “Oh my gawd!” not far behind). The most delightful voicework and funniest characters come from Hannibal Buress’ Edward, Keegan-Michael Key’s owl Judge Peckinpah and Maya Rudolph’s hippie therapist bird Matilda.

If Angry Birds fully embraced its message, it could have been a refreshing surprise. But like the mindless video game that inspired it, there’s little here beyond fleeting satisfaction.