Monsters, Inc was one of Pixar's first ever animated movies and 21 years later it's still one of its most beloved.
Many of us grew up watching the loveable top scarer Sulley and his witty best friend Mike Wazowski as they navigated their friendship and formed the most heartwarming relationship with Boo, the little girl who had somehow managed to sneak into Monstropolis with Sulley after he tried to (unsuccessfully) scare her.
Sweet and innocent, right? Wrong. Like many movies, Monsters, Inc has been subject to some heavy discussion after a pretty disturbing fan theory was posted on Reddit. Even Disney isn't safe – and this is definitely one of the craziest we've seen.
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It posits that before the monsters harvested the screams of children to generate their city, they harvested their blood. Yep, you read that right. Children's blood.
Reddit user curlyquirkycolorful does provide some method to the madness, and reveals that the concept came to them when they noticed a Monsters Incorporated commercial playing on Sulley's TV. In the commercial, we hear:
"Carefully matching every child to their ideal monster, to produce superior screams refined into clean, dependable energy."
Since the movie is heavily focused on how the city is now powered by clean energy, the theory suggests that Monstropolis must have previously been powered by a dirtier energy.
"Something dirtier and literally non-renewable that the monsters have moved away from as a society: the blood of children," writes the user.
After all, clean energy is a real-world concept. We have clean energy like solar power and dirty, CO2-producing energy, such as oil and coal.
If clean energy exists in Sulley and Mike's world, then it makes sense that the dirtiest energy was used first: children's blood (gross). Next, their screams are harvested instead as a cleaner form of energy, just like how we use renewables.
Lastly, at the end of the movie, the cleanest form of energy is used: children's laughter.
Just like how our cleanest form of energy is solar power, the monsters have continued to move away from dirty energy as they discover cleaner forms. In summary, they went from harvesting children's blood to harvesting their laughter. Yikes.
It's kind of disturbing, we know, but it does kind of make sense too.
Want to decide for yourself? Watch Monsters Inc on Disney+. Haven't got an account? Sign up now for only £5.99 a month.
Social Executive, Entertainment Portfolio After completing her joint honours degree in Journalism and English Literature at Cardiff University, Iona joined Digital Spy as a Content Production Intern in 2022, where she wrote across both news and features, specialising in TV and movies. Following her internship, Iona continued contributing to the site as a freelance reporter, becoming social executive for the Hearst UK entertainment portfolio in summer 2025. Iona now leads the DS social channels, covering red carpets with stars such as Paul Mescal, Austin Butler, and more.
