Henry J. Waternoose III, more commonly known as Mr. Waternoose or simply Waternoose, is the hidden main antagonist of Monsters, Inc. and a minor character in Monsters University. He is the former chairman of the company, Sulley and Mike's former boss, best friend, and father figure and Randall's former leader and boss.
- Due to the line "I never should have trusted you (Randall) with this" Waternoose is often mistaken for Randall's henchman and the films secondary antagonist however this is not true. Waternoose is the chairman of the Monsters Inc company and therefore holds authority over all workers (including Randall). What he meant was he regrets assigning Randall the task of aiding him in his scheme. This was proven when after Sulley saves Boo from the scream extractor (shortly after he said that) Waternoose is shown ordering Randall to stop Sulley from escaping with Boo and shortly after that when Mike is trying to explain everything that's going on to Celia at one point he says "Waternoose has this secret plot" specifically stating that Waternoose is the mastermind and not Randall.