On Bird Island, a peaceful community inhabited solely by happy, flightless birds, Red, a bird with a temper problem, often feels like an outsider. After a court-ordered anger management class fails to quell his outbursts, Red still struggles to find his place among the cheerful inhabitants. His quick temper gets him into trouble, further alienating him from his fellow birds. The loneliness only fuels his frustration, and Red continues to grapple with the community that seems so inherently different from him.

The birds' tranquil life is thrown into disarray when a mysterious boat docks at their island, carrying green pigs led by Leonard. The pigs charm the birds with their friendly demeanor and introduce advanced technology and fun-filled games, quickly winning the trust of the bird community. However, Red is suspicious of the pigs' intentions and, alongside his anger management class companions Chuck and Bomb, sets out to discover the true reason behind the pigs' unexpected visit. His distrust leads him on a quest that begins to unravel the true nature of the pigs' plans for Bird Island and its inhabitants.