Buster Moon is an eternally optimistic koala who hosts the world's greatest singing competition to save his crumbling theater. Stepping into the spotlight are Rosita, an underappreciated mother of 25 piglets desperate to unleash her inner diva; Ash, a punk rock porcupine with a beautiful voice behind her prickly exterior; and Johnny, a young gorilla looking to break free of his family's felonies.