Creating a follow-up to Toy Story 2 is a daunting task, and topping it is even more so. Pixar and Disney may not have accomplished the latter, but Monsters, Inc. is still a tremendously enjoyable film in its own right. This time, instead of dealing with toys coming to life when children are away, the movie deals with the imaginary monsters lurking in the closet. It turns out that these monsters are not imaginary. The screams of children provide them with the energy they need to power their city, Monstropolis. The catch is that monsters are deathly afraid of children. They believe that children are toxic to them. Monsters, Inc. is the premiere company for collecting power, and James "Sully" Sullivan (John Goodman, My First Mister, One Night at McCool's) is the lead scarer. Together, with partner Mike Wazowski (Billy Crystal, American Sweethearts, Adventures of Rocky and Bullwinkle), they dutifully scare many children each night.

One night, a child comes through into their world. Boo (Mary Gibbs) lands into the hands of Sully and Mike, who are doing all they can to hide their presence. Monsters, Inc. teetering on the edge of solvency, and boss Henry J. Waternoose (James Coburn, Intrepid, The Good Doctor) wants nothing to go wrong. If authorities discover a child on the premises, it will shut the company down. Sully and Mike's initial fear of Boo gradually gives way to friendship, then love. Here, the story takes a surprisingly dark turn. This involves Randall Boggs (Steve Buscemi, Ghost World, Domestic Disturbance), Sully's main competition. He is the one responsible for Boo's presence in the factory, and has a nasty plot to increase the collection of energy. Jill Culton, director Pete Docter (Winter), Ralph Eggleston (Dinosaur), Dan Gerson, Jeff Pidgeon, Rhett Reese, and Andrew Stanton (Toy Story 2, A Bug's Life) all have story credit, but even with so many people the plot remains cohesive.

Docter and co-directors David Silverman (The Road to El Dorado) and Lee Unkrich (Toy Story 2) stick with the successful Pixar/Disney formula; great computer animation and an enchanting storyline. Pixar again leapt forward in computer generating power. They have the ability to render thousands of hairs individually, so when Sully moves, his animated hairs look and move like actual fur. The rest of the characters and backgrounds are impressive, and do not get in the way of any story development (see Final Fantasy). In fact, sometimes many of the locations look real, with the exception of the various monsters walking around.

Aside from the slight dark diversion, Monsters, Inc. retains much of the witty humor that Pixar enjoys that both children and adults can enjoy. It was an ingenious twist to have the monsters afraid of the children. The only element where Monsters, Inc. does not surpass its predecessor is in the emotional depth. It does have enough to bring tears to the eyes of some, but is nowhere near the level of emotion present in Toy Story 2. Before the film is an enjoyable short entitled For the Birds, about some birds sitting on a telephone wire. It is thoroughly familiar and a couple minutes in length, but still highly enjoyable.