The city of Monstropolis in the monster world is powered by energy from the screams of human children. At the Monsters, Inc., factory, skilled monsters employed as "scarers" venture into the human world to scare children and harvest their screams, through doors that activate portals to children's bedroom closets. It is considered dangerous work, as human children are believed to be toxic. Energy production is falling because children are becoming less easily scared, and Henry J. Waternoose, the company's chairman, is determined to find a solution to the problem. James P. "Sulley" Sullivan and his best friend, Mike Wazowski, are the organization's top employees, but their chief rival, Randall Boggs, is close behind.