Trivia: At one point early in production, the film was going to be slightly retooled in order to make it the third entry in the "Cloverfield" franchise, following "Cloverfield" and "10 Cloverfield Lane." Eventually, this idea was dropped, and the movie was left as a stand-alone film.
Trivia: When Dwayne Johnson signs to George to calm him down, he says "it's me." The sign he makes on those words is for "Rock," a reference to his stage name "The Rock." (00:15:25)
Trivia: When Ralph and Venellope arrive in the internet they are bombarded with pop up ads. One of those ads features a picture of a woman with short brown hair. That woman is Aunt Cass from the Disney animated film, "Big Hero 6." In addition, Baymax from that movie makes a cameo appearance at, "Oh My Disney!"
Trivia: The spears shown in the lab are from Predator 2 and Alien vs Predator.
Trivia: Author of the novel Kevin Kwan has a cameo in the montage 'Who is Rachel Chu'.
Trivia: The Philosopher's Stone from the first Harry Potter film is visible inside Nicholas Flamel's locker.
Trivia: While Bill Foster, played by Laurence Fishburne, is teaching the class, the words "Matrix" can be seen on the blackboard behind him, referring to the film series Laurence Fishburne starred in.
Trivia: Julie Murphy, author of the the book "Dumplin'", makes a cameo as one of the cheering patrons at the drag bar in the last scene.
Trivia: There is a message left at the end of the credits of the film reading "The staff at the Hotel Artemis hope you enjoyed your stay and that you'll return soon." (01:33:20)
Trivia: When the other guys ambush Jerry at the Deer Hall, he starts narrating to himself as things happen in flashes of slow motion. This is a direct spoof/reference to the 2009 Sherlock Holmes movie where RDJ's version of the character does this same thing as he analyzes a fight or sequences, predicting the outcome. (00:24:45)
Trivia: When a member of the resistance destroys a truck with his RPG, the "Wilhelm scream" can be heard.
Trivia: The real RL Stein makes a cameo appearance as the principal Mr. Harrison who presents Sonny with his science award at the end of the film.
Trivia: The animators created many small flaws in the film in order to emulate the looks of old comics. This includes color separation and a slight double-image effect in certain scenes to replicate imperfect comic-printing techniques. While the effect was intentional, many film-goers who saw the movie in 2D actually complained about these effects, thinking they were accidentally sold tickets to a 3D movie. (Especially due to the double-image effects).
Trivia: Spoilers. You can briefly see at one point that Margot's high school mascot is an anthropomorphic catfish. In internet slang, "catfishing" is when someone pretends to be someone else online in order to "lure in" others. This is a very subtle clue to the ending, in which it is revealed that the user "fish_n_chips" was a boy who was "catfishing" Margot online.
Trivia: When Watson falls from a tower in the museum courtyard, he yells a Wilhelm scream.
Trivia: Contemporary or modern-day altered version of the "BTK" (Bind, Torture, Kill) serial killer - Dennis Rader - who murdered at least ten women from 1974-1991 in the Wichita, Kansas area. Rader was arrested in 2005 and received ten life sentences, but the "Clovehitch Killer" was killed by his son and made to look like an accident or suicide.
