"Monsters, Inc." is set in Monstropolis, a thriving company town where monsters of all shapes and sizes reside. Sulley and his wisecracking best friend Mike Wazowski are the top scare team at Monsters, Inc., the largest scream-processing factory. The main power source in the monster world is the collected screams of human children-and at Monsters, Inc., an elite team of scarers is responsible for gathering those precious natural resources. Believed by monsters to be toxic, children are strictly forbidden from entering Monstropolis. But when a little girl named Boo accidentally follows Sulley back into his world, he finds his career in jeopardy and his life in utter chaos. So pals Mike and Sulley plot to rectify the mistake and return Boo to her home. But when the trio encounters an unexpected series of complications, they become embroiled in a cover-up catapulting them into a mystery beyond their wildest dreams.