'The Angry Birds Movie': 5 things we learned

Why are the titular birds in the crazy-popular Angry Birds mobile game so ticked off at a bunch of green piggies?

That question that's been on (about 3 billion) gamers' minds will finally be answered in 3D animated comedy The Angry Birds Movie, which is out May 20 and features the voices of Jason Sudeikis, Bill Hader, Josh Gad and Danny McBride.

We don't want to spoil exactly what's so anger-inducing for a bunch of round, flightless birds, but here are 5 things we learned at an Angry Birds Movie "Sneak Beak" event at Sony Pictures that featured producers, directors and voice actors:

1. The birds weren't always so angry

Yep, according to producer John Cohen, who worked closely with Angry Birds game creator Mikael Hed, the story begins with a bunch of happy, flightless birds hanging out on an island. There are only a few birds-- namely Red (Sudeikis), Chuck (Gad) and Bomb (McBride)-- who are dealing with some things in an anger management class.

2. The birds in the movie do not play the 'Angry Birds' game

The birds' island is "naturalistic," said Cohen. There are no cell phones, which means no mobile apps and games. There are, however, places where birds can get feather extension and participate in mommy & me classes, with their eggs.

3. The pigs live in a world with 'Ham-ilton'

A spoof Broadway smash, there are advertisements in the pigs' island for Ham-ilton starring Kevin Bacon. You can expect plenty more pop-cultural jokes like that: The movie was written by Jon Vitti from The Simpson.

4. Sudeikis, Gad and McBride can relate to their characters

Sudeikis said that, like his character who's "angry from the jump," he, too, has a temper. "I get ticked off from the person I get to sleep next to, to my supportive family... my bingo card is full," he joked.

Gad said that he also would also be able to relate to the birds' anger, if, hypothetically, a "reality TV star could be the next President of the United States."

McBride channels his inner anger when Waze tells hims to "make a left over four lanes of traffic."

5. Hader's pig voice sounds like... 'my dad'

Hader, who voices the pig Leonard, tried out a few different sounds for his character. At first, he went with a Robert Preston/Music Man-sounding voice, but in a second session, filmmakers asked him, "Do you have something else?"

"So we found this 'Hee Haw'/'Music Man' ... very jolly and excited. It's basically... my dad."