Remember those days when everyone you knew with a smartphone was playing Angry Birds all day and all night? It was one of the first mobile games to truly conquer all corners of the market -- from little kids to grown adults, if you weren't already addicted to Angry Birds then why even exist?

Then, like things always do, we moved on to other feverishly addictive games -- but the appetite for Angry Birds was still there, so much so that a movie was announced. Due out on May 20, 2016, Angry Birds features a voice cast stuffed with some very, very funny people, including Maya Rudolph, Peter Dinklage, Jason Sudeikis, Danny McBride, Bill Hader, Jillian Bell, Keegan-Michael Key, Tony Hale and Josh Gad.

And now we've got the film's first trailer, which promises to answer the one question us Angry Birds fanatics have always had: Why, exactly, are these birds so angry?

Though the first trailer only really serves to introduce the main characters (primarily the red bird, yellow bird and bomb bird), fans of the mobile game will chuckle at the way the film works in their quirks. Like how the bomb bird randomly explodes at inopportune times, or how the red bird is just forever pissed off -- probably because he doesn't have any cool tricks like the others.

Yes, the pigs are involved, and we already love 'em cause their leader is voiced by Bill Hader. We assume we'll also soon learn why the birds become so angry with the pigs, and eventually build elaborate slingshot setups to defeat them.

Angry Birds slings into theaters on May 20, 2016. What do you think of the first trailer?