Warning: The following article contains minor spoilers for Toy Story 4, in theaters now.
Like most Pixar movies, Toy Story 4 has plenty of references to the studio's other films. The film reportedly contains at least one callback to every other Pixar movie, with many of those callbacks coming in an antique shop filled with thousands of unique items.
While flourishes like that can make Toy Story feel like part of a larger interconnected universe, director Josh Cooley told JoBlo that the mother of Bonnie, Woody and Buzz Lightyear's current owner, could be seen reading a book that rejects that kind of inter-connectivity.
"While the title is obscured in the final cut of the film, the book she is reading is called Beyond Infinity: Debuking Theories of a Shared Universe," Cooley said.
While the book's title and the rest of the film's Easter eggs seem to send a mixed message about shared universes, they both simultaneously embrace and reject the Pixar Universe Theory, a popular fan theory that claims all of Pixar's films take place in a shared universe.
To briefly summarize, the Pixar Theory claims that humanity created artificial intelligence powered by emotional energy to stay ahead of hyper-intelligent animals. After humanity was forced to flee Earth, the theory claims that animals and A.I. beings continued to evolve until they ran out of emotional energy. According to the theory, the monsters of Monsters Inc. travel to the past to harness the emotional energy of frightened children.
While the Pixar Theory ties films as diverse as The Incredibles, A Bug's Life and Inside Out together, it still doesn't cover the full theoretical scope of the Pixar Universe.
In Toy Story, a Binford Tools toolbox can briefly be seen in the background of Sid's room when he straps a firecracker to Buzz Lightyear. That fictional tool company plays a major role in the '90s Tim Allen sitcom Home Improvement, and that connection loosely links the worlds of Pixar and that fondly-remembered sitcom together.
However, Home Improvement is also connected to an even more famous fan theory, the Tommy Westphall Universe. That theory stems from the series finale of the '80s medical drama St. Elsewhere. The final moments of the series revealed that the entire show had taken place in the imagination of a young boy named Tommy Westphall.
In the years after the finale, fans began to connect the dots between the cameos and guest stars from other shows who appeared in St. Elsewhere. By the finale's logic, shows like Cheers were also part of Tommy's imagination since they crossed over with St. Elsewhere at one point or another.
When that same logic is applied over and over again, hundreds of shows and movies, ranging from The X-Files to Buffy the Vampire Slayer and the universes of Star Trek, Doctor Who and Aliens, could all theoretically take place alongside the entire Pixar Universe within Tommy Westphall's mind.
Over the past decade, cross-franchise productions like Kingdom Hearts, Disney Infinity, The Lego Movie(s) and Lego Dimensions have brought a staggering number of disparate franchises together, which takes these kinds of theories to truly ludicrous new heights.
For instance, last year's Kingdom Hearts III featured characters from Pixar films like Toy Story and Monsters Inc. interacting with characters who are connected to the vast worlds of the Final Fantasy gaming franchise. That game also includes a level based on Big Hero 6, a film that could be considered part of the larger Marvel multiverse, which opens up paths to Street Fighter, the DC Universe and dozens of other fictional realms.
Taking to their utmost extremes, the Pixar Universe Theory and the Tommy Westphall Theory could probably tie every major franchise in pop culture together through one loose technicality or another.
While trying to figure out how The Simpsons, Mortal Kombat and Toy Story are connected is an amusing exercise in mental gymnastics, all of these connections ultimately don't add up to a meaningful narrative.
Despite that, these fan theories about shared universes make a chaotic cultural landscape filled with thousands of ideas feel a little bit more cohesive. While Pixar's kid-friendly films will probably never turn into an explicit meditation on the rise and fall of humanity and the nature of artificial intelligence, the Pixar Universe Theory makes all of those films richer texts that reward deep dives and repeated viewings. These theories make static pieces of art interactive in a way that lets fans wield some kind of influence over the stories they love.
While relatively small teams of artists created these worlds, fans drew the lines between them to make a universe. As long as those artists keep creating, theories and ideas like the Pixar Universe will only continue to expand.
Directed by Josh Cooley, Toy Story 4 stars Tom Hanks, Tim Allen, Joan Cusack, Keanu Reeves, Annie Potts, Don Rickles, Estelle Harris, Wallace Shawn, John Ratzenberger, Jeff Pidgeon, Blake Clark, Keegan-Michael Key, Jordan Peele and Tony Hale.