Monsters, Inc. is a 2001 computer-animated film and the fourth feature-length buddy comedy film produced by Pixar Animation Studios. It was directed by Pete Docter, co-directed by Lee Unkrich and David Silverman, and was written by Jack W. Bunting, Jill Culton, Pete Docter, Ralph Eggleston, Dan Gerson, Jeff Pidgeon, Rhett Reese, Jonathan Roberts, and Andrew Stanton.
The film was released to theaters by Walt Disney Pictures in the United States on November 2, 2001. It was a commercial and critical success, grossing $562,816,256 worldwide. Rotten Tomatoes also reported positive reviews with a fresh 96% approval rating. The film was re-released in theaters in 3D on December 19, 2012. A prequel titled Monsters University was released on June 21, 2013 and is also Pixar's first prequel film made to one of their original films.
A television spin-off series titled Monsters At Work was announced during a Disney press release on November 9, 2017. The spin-off series will be a part of Disney+. It is slated to be released in Spring 2021.
The movie opens with a young kid laying in bed, frightened while looking at his closet door. Next thing he knows, a monster is standing beside him. The boy sits up and the scared monster screams, trips, and falls. Suddenly, alarms go off, lights come on, and we discover that it is a scaring practice going on in the training room of Monsters, Inc, the power company of Monstropolis. The head of the power company is Mr. Waternoose (James Coburn), who is training new monsters to scare kids. It seems that Monstropolis gets all its power from screams, and he has a whole squad of monsters whose job it is to scare kids at night and collect their screams.
It is a very complicated system they have for collecting the screams. They have a warehouse full of closet doors, and they call up a particular door for whichever room they want. The door is sent by a hanging conveyor belt and placed in front of the Monster on the "scare floor". When the door is opened, the monster is in another room in another part of the world. If for any reason there is a problem with that particular room, the door is shredded.
One other thing... Monsters are actually more scared of the human kids than the kids are of them. If any part of the human world enters the monster world, the CDA (Child Detection Agency) comes in and decontaminates the place and monster bringing it in.
The top scarer is James P. "Sulley" Sullivan (John Goodman). He is the best in the business. With the help of his assistant Mike Wazowski (Billy Crystal), they are about to break the record for most screams collected. In 2nd place on the list is Randall Boggs (Steve Buscemi). He will stop at nothing to be in first place. One night, Mike is in a hurry to get out since he has a date with his girlfriend Celia Mae (Jennifer Tilly) to celebrate her birthday. He forgets to finish his paperwork, so Sulley says he will go back in to get it. Sulley goes back to the scare floor and it is deserted, except for one door, which is still on the floor. Sulley is curious, so he peeks inside the door. Inside is a cute little girl who is not scared at all of Sulley and in fact, thinks he is cute. Sulley is terrified of her and runs out the door, back to the scare floor. He hears a thumping sound and realizes that the girl, playing with his tail. He shakes her off and runs into the bathroom. When he looks into the mirror, he discovers that the girl is on his back.
Sulley wants to take the girl back to her door, but when he goes back to the scare floor, Randall and his assistant are looking in the door and are upset that the girl isn't there. They send the door back to the door warehouse. Sulley places the girl in a suitcase and heads out to the restaurant to find Mike. He interrupts Mike and Celia's dinner and shows Mike what he has in the suitcase. The girl gets out of the suitcase, and the whole restaurant is in panic. The CDA arrive, and the patrons are screaming and running, terribly afraid of the girl.
Sulley scoops her up and he, the girl (whom he names Boo) and Mike run to their apartment. They try to hide her as the helicopters are searching outside, but whenever she cries, the lights come on brighter. Though when she laughs, the lights come on super bright. In fact, she laughs so hard once that she blows the fuse to the building. The next day they put a monster costume on Boo and bring her to the factory. Their goal is to find her door and bring her back without anyone noticing. Unfortunately, Randall and Fungus are also there searching for Boo. It made the news about Boo and the restaurant, and they are sure it is their fault.
Eventually, Randall convinces Mike that if they bring the girl back to the scream floor, the door will be there waiting for them. Mike tells Sulley this and right before they enter, Sulley figures out that Randall would never want to help them so it must be a trap of some kind. Mike thinks he is crazy and runs in and starts jumping on Boo's bed. Suddenly, a box comes down and traps Mike inside. Sulley hides as Randall and his assistant take the box to another room in the warehouse.
In the basement, Randall reveals to Mike that he has built a torture machine ("Scream Extractor") to extract children's screams from their lungs (which would make the company's current tactics redundant). Randall straps Mike to the chair for experimentation and starts it up to try not to let him talk, but Sulley unplugs the machine. He then takes Mike and, along with Boo, runs to find Mr. Waternoose. Waternoose is proud of the two of them for discovering Randall's evil plan. The most important thing is, however, getting the girl back home. They head to the scare floor and Waternoose calls up Boo's closet door.
Sulley and Mike say that it is the wrong door. Mr. Waternoose says he knows... it is not the door for her, but for them, and with that, he pushes the two through a door that leads them to the snowy peaks of the Himalayas. Waternoose has actually been helping Randall in the plan this whole time. They have been banished from Monstropolis. Sulley gets the idea that if they go to the closest town, all they have to do is to find any kid's closet and return to Monstropolis.
Back to the scare floor and out of a door comes Sulley. In Randall's lair, he and Mr. Waternoose argue over Randall's negligence that forced Waternoose to banish Sulley, feeling regretful about it. Sulley rushes to the secret room and there, trapped in a chair is Boo, about to have her screams sucked out. Sulley destroys the machine, takes Boo, and rushes her to the scream floor to find her door with Randall right on their heels. They race from door to door, trying to find a shortcut to Boo's door in the warehouse. Each time they go through a door, they are in another part of the world.
They finally trap Randall in a door that leads to a trailer in the Bayou. The kid in the trailer calls out to his mother that another alligator has come inside and the boy hands a shovel to his mother who then clubs the "gator". Waternoose chases Sulley and Boo through a door that appears to be Boo's. Waternoose confronts Sulley and declares that he will do anything to save the company, even if it means kidnapping children. Suddenly, an alarm sounds and all the lights come on. They are not in Boo's room after all. They are actually in the training room from the beginning of the film and Waternoose has just confessed in front of everyone.
They are all shocked, and the CDA arrest Waternoose after hearing his confession. The actual head of the company was Monsters Inc's dispatcher Roz, who has been undercover for over two years trying to expose Randall and Waternoose's plan. She congratulates Sulley and gets the key to bringing Boo's door down.
Sulley, who has grown quite fond of Boo, tucks her in her own bed, plays with a few of her toys with her and then goes back to his own world, shutting the door behind him to never see Boo again. The door is shredded. The next day, the workers are now leaving the factory for the last time. It is closing for the final time because kids just cannot be scared anymore. Sulley suddenly has an idea and races back inside with a plan to end the company's energy crisis.
The next scene is Mike entering a kid's closet door. He sits down in front of the kid and starts doing a standup routine as a comedian. The kid starts laughing at Mike after he swallowed his microphone and then burps loudly. Finally, the power generated is enormous. It turns out that a child's laugh has ten times the power of a child's scream. The factory is saved. However, Sulley is still sad as he still misses Boo. Mike then tells him that he has a surprise.
In the testing room, it is revealed the Mike had successfully re-pieced Boo's door together. All it needs is one more piece. Sulley lifts some papers on his clipboard and pulls out the last piece of Boo's door, which he kept as a memento. Once Sulley places the last piece into the door, the light above the door illuminates. Sulley slowly opens the door and looks to see if Boo is around. Boo then says "Kitty" and Sulley smiles in delight for seeing Boo once more.