The first half-hour or so suggests that there was a very real possibility of doing something clever with the idea of turning the popular app and video game of “The Angry Birds” into an animated movie. It was, after all, already the basis of a series of short television cartoons. Unfortunately, the promise dissolves as the picture turns into an action adventure of the most conventional, derivative kind. The angry birds have always been flightless, of course; their first feature is distinctly earthbound.

The movie begins by introducing Red (voiced by Judas Sudeikis), a grown-up orphan who’s mad at the peaceful, insufferably sweet world of Bird Island. Working as a curmudgeonly birthday clown, he gets into a fight with a disappointed client and winds up in court—not for the first time, it appears. He’s sentenced to the max by the unforgiving judge—anger-management classes with therapist Matilda (Maya Rudolph). It’s there that the crabby fowl meets ultra-speedy, full-of-excuses Chuck (Josh Gad), slow-witted, ready-to-explode Bomb (Danny McBride) and oversized, threatening growler Terence (Sean Penn).

It’s here that the trouble with “The Angry Birds” begins. Red is an amusing character—a sort of animated Ralph Kramden—but his sidekicks are less so. Gad was able to make Olaf the snowman in “Frozen” cheerfully goofy, but Chuck comes across as irritating, and presenting him as a bird version of Quicksilver (one sequence even rips off Bryan Singer’s amazing introduction of that X-Men speedster) never reaches the level of lunacy that was obviously intended. McBride, an acquired taste anyway, doesn’t do much with Bomb, and while Penn’s inarticulate rumblings are a good in-joke, it’s a gag that wears out its welcome. Nor is Rudolph particularly inspired.

Still, one can imagine that the movie might have worked had it stayed a portrait of a guy in conflict with his own community. Instead it quickly introduces the Piggies, lime-green interlopers from another island led by a porcine Barnum (Bill Hader) who seduces all the birds—save the suspicious Red, of course—with insincere offers of friendship and flashy Las Vegas-style floorshows. The act is merely a cloak for the pigs’ real mission—to steal the birds’ eggs before they hatch and take them back to Pig Island for a big feast. When he and his friends fail to foil the theft, Red leads an expedition to the enemy stronghold to save their unborn from being eaten. (When you put it that way, of course, you can read all sorts of hidden subtexts into the story. Many will, one supposes.)

With this protracted military-style assault, which seems to take up fully the last third of the picture, things deteriorate further, especially since it involves the reappearance of Bird Island’s legendary founder Mighty Eagle (Peter Dinklage), an overweight, self-aggrandizing sluggard who’d retired to a cave at the pinnacle of the place. In a sequence that seems interminable (and includes the worst, most extended bit of potty humor in the movie), Red, Chuck and Bomb visit him to ask his help, and in the end he screws up his former courage to intervene when the situation is at its most dire. Dinklage tries hard, but ultimately Mighty Eagle is a pretty tiresome figure, and his presence in the big finale weighs it down rather than giving it a lift, despite the fact that he alone can fly.

Writer Jon Vitti tries to liven up “The Angry Birds” by filling the dialogue with puns, most of the groan-worthy variety but some that may well raise parents’ eyebrows in dismay (what will the kids make, for example, of Red’s “Pluck my life!” moment?). But neither they, nor the deliberately coarse sight gags that periodically occur, make up for the feeble plotting, which might have worked in interactive format or brief cartoon spurts but overstays its welcome in a ninety-minute dose. The voice work is okay—Sudeikis nails Red’s mixture of gruffness and vulnerability, and though the rest overplay the hands they’re dealt, that’s to be expected given the lines they’re required to deliver. The animation is fine, and game aficionados will doubtlessly appreciate seeing the figures they’ve toyed with brought to the big screen with such unaccustomed opulence (in 3D, no less). But as usual, technical craftsmanship can’t compensate for a failure of narrative imagination.

Neither bad enough to make you furious nor good enough to be memorable, “The Angry Birds” demonstrates once more how difficult it is to craft something special from a preexisting commercial property.