We all remember the heartbreaking moment Boo excitedly runs to open her wardrobe in Monsters, Inc. in the hope of seeing Sulley - only to be faced with an empty cupboard.
Thankfully, Mike Wazowski helps his best friend rebuild the door that was destroyed so the pair can be reunited - but some fans now have a theory that Boo took matters into her own hands.
The theory was discussed by the Just The Nobodys podcast and shared on the TikTok account @Justthenobodys, where the hosts revealed that Boo might actually appear in another Pixar film later on in her life.
They say: "So you know like in Monsters, Inc. how all the monsters travel through doors that go to a random kid's room to scare them?
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"There's a theory that after Sulley and Mike left Boo, she missed them a lot and always wanted to go and try find them again."
They say that little Boo discovered a way to use magic to travel through doors, just like the monsters do, to go anywhere she wants.
And there's another Pixar character who they say does just that - the evil witch from Brave.
They continue: "Boo from Monsters, Inc. is actually the witch from Brave and she also has a carving of Sulley on a piece of wood.
"And she has a model of Randall from Monsters, Inc.
"On her desk, there's also a wood carving of the Pizza Planet truck (from Toy Story), which shows that she can time travel, because in Brave the Pizza Planet truck did not exist yet."
The video racked up more than three million views, as one person commented to say: "This ruins my childhood but at the same time I love your theories."
A second wrote: "OMG. Gosh, this actually makes so much sense."
And another added: "I wish I could un-hear this now."
What do you think of the theory? Let us know in the comments.
