Boo is the tritagonist from Disney's 2001 computer-drawn feature Monsters, Inc. She is a 2 1/2 year old human girl who gets stuck in the monster world, and Sully and Mike have to take back to her world. She was voiced by Mary Gibbs.

Appearance and PersonalityEdit

Physical AppearanceEdit

Boo is an adorable and very beautiful 2 1/2 year old girl. She is very short, due to her age, and has brown hair, which she wears in pigtails tied with purple bands. Boo normally wears a big pink shirt, purple leggings and white socks, but also wears a purple monster costume when she is in disguise.


Despite her cuteness and beauty, Boo acts like a regular toddler, and can be naive and curious. She also has a lot of energy. She is normally shown to be a very happy girl, but can be shown to be scared at some points, especially of Randall. She is also in potty training.


Monsters Inc.Edit

Boo is first shown following Sulley, after coming out of her door, into the monster world, because Randall intended to kidnap her. Sulley tries to take her back to her door, but the door leaves without her. After several misadventures, he attempts to take the girl to Mike, who is enjoying a romantic dinner with his girlfriend at Harryhausen's. The girl escapes and is seen, causing mass panic (as all the monsters are afraid of children) and alerting the Child Detection Agency (CDA). The two grab her and barely make it home and ends up at Mike and Sulley's house.

At first, Sulley and his friend Mike, decide to get rid of the kid, but they eventually realize the kid is not dangerous, and decide to take her back to her door. They disguise the girl as a monster, to sneak her into Monsters Inc.

Sulley becomes attached to the girl (and calls her "Boo", as her habit of saying "Boo!" all the time). When Sulley realizes that Randall wants to capture Boo, and use her screams to become the best scarer, they decide to go ask Mr. Waternoose, the head of the company, for help. Mr. Waternoose, not realizing that Sully has the child orders him roars in front of a child used for simulation. Sulley does roar, and scares Boo. Sulley tries to apologize to Boo, but she is too terrified of him and runs to cower underneath Waternoose's legs. Waternoose, who has

Boo in her monster costume

caught sight of Boo, decides to take care of her before anything worse happens. After he and Randall banish Mike and Sulley to the Himalayas, they proceed with extracting screams from Boo by using the Scream Extractor. However, Sulley arrives at the last moment to disable the device to free Boo. Mike catches up with them, and they rush back to Scare Floor F, with Randall in hot pursuit. Randall chases them to a large chamber where thousands of doors to the human world are kept. Mike and Sulley then make Boo laugh to activate the doors, then they go through them, exiting the monster world and entering back into it, in order to

Boo and Sulley

lose Randall and reach Boo's door. Just as it looks like Mike and Sulley have lost Randall, Boo suddenly slips off from Sulley's arms, and Randall reveals that he has caught her. Sulley manages to catch up with Boo, but then Randall ambushes Sulley. Just as Randall is about to finish Sulley off, Boo suddenly jumps on Randall and beats him with a baseball bat. Boo has managed to overcome her fear of monsters, especially Randall. After Mike and Sulley banish him through another door, disable that door, and let it fall to the bottom of the chamber to ensure that he will never return, Boo blows a raspberry directed at the shattered door. They open Boo's door, only to realize that the power has went out, but then, the door moves back to Scare Floor F, where Waternoose and the CDA agents are waiting. Mike runs off with Boo's monster costume as the agents goes after him while Waternoose notices Sulley with Boo and her door and chases them to the simulation room, where he is lured into a trap set by Mike. Mike exposes Waternoose's plot to kidnap a thousand children (possibly including Boo) to satisfy his own agenda to the agents, who then turn on Waternoose and arrest him. Immediately thereafter, Roz, revealed to be Agent 001 of the CDA, enters and decides that Boo's door is to be destroyed after she is safely returned to her room in order to ensure that she will never come back again. She lets Sulley have 5 minutes to say goodbye. After Sulley takes her back to her room, and tucks her into her covers, they hug, and say their goodbyes. take a possibly one last look at each other, then after Sulley closes the door, Boo

Boo and Mike Wazowski

then opens it to possibly surprise him, only to find her closet instead and Sulley nowhere. After her door is shredded, Sulley feels sad that he'll never see Boo again and keeps one of the splintered pieces from her door as a memento.

At the end of the film, Mike brings Sulley (now the new CEO of Monsters, Inc) a surprise, which turns out to be Boo's door reassembled. The door becomes functional when Sulley places the piece he has kept, and he opens it to see Boo, who (although off-screen) recognizes him by saying, "Kitty!" This gives Sulley a surprised grin on his face as the film closes.

Toy Story 3Edit

An older version of Boo is briefly seen in Toy Story 3. She is seen playing with a blue cat (Boo's nickname for Sulley is "Kitty") and says "Boo", possibly reenacting a scene from Monsters, Inc. Judging by the years

Boo in Toy Story 3 (on the left) compared to her appearance in Monsters Inc (on the right)

that passed, theres nothing that suggest that Boo and the Sunnyside Girl aren't one and the same.