1.When Hercules first walks into Phil's cabin in Hercules, he whacks his head on the mast of "The Argo." In the original myth, Jason (the captain of the Argo), was killed when that same mast hit HIS head.
2.During the wild party scene in Bruce Almighty, Bruce leans on a golden calf, referencing "the sin of the calf" from the Bible, in which a golden calf signified a "false god."
3.Every time Helen is referenced in the John Wick series, there is a daisy present in some form, down to the original puppy's name being "Daisy."
4.In Ratatouille, critic Anton Ego's typewriter is shaped like a skull to foreshadow his harsh, restaurant-killing reviews.
5.When Bruce Wayne kicks all of the guests out of his birthday party in Batman Begins, he says "To all of you phonies, you two-faced friends, you sycophantic suck-ups who smile through your teeth at me, please leave me in peace. This is not a joke." A sentiment that foreshadows both Two-Face and the Joker's appearances in the next film.
6.Marvin the Martian was chosen to be the basketball referee in Space Jam because he is both a toon AND an alien, and is therefore the "most impartial."
7.The rubble left by the Asgardian mural in Thor: Ragnarok foreshadows the injury Thor receives later.
8.The potion Ursula takes to transform in The Little Mermaid has a butterfly in it. Her human name is "Vanessa," which is a genus of butterfly.
9.Instead of swearing, the characters use the word "cuss" in Fantastic Mr. Fox, so one of the buildings seen in the background has the word "CUSS" as spray-painted graffiti.
10.A knocked over bottle of LITERAL poison can be seen next to the sink in Matilda while her mom is bathing her, an early indicator of the parents' negligence and disdain for their daughter.
11.In Toy Story, Andy wrote his name with a backwards "N" on Woody's boot, but the "N" is correct on Buzz Lightyear's boot, which is meant to show he's growing up.
12.Tony Stark has an alternate A.I. named "Tadashi" in Avengers: Age of Ultron, which is a reference to Baymax's program chip and creator in Big Hero 6.
13.The door Luke uses for his hut on Ahch-To in The Last Jedi is salvaged from his old X-Wing fighter.
14.In Halloween (2018) a circular scar is visible on Michael Myers neck, right where Laurie Strode stabbed him with a knitting needle 40 years earlier.
15.When Maurice comes to the crossroads in Beauty and the Beast (1991), the sign pointing to the sunny, safe path faintly reads "Anaheim," where Disneyland is located.
16.When riffling through applications for the X-Force in Deadpool 2, you can see Ruth Bader Ginsberg's headshot with "Notorious R.B.G." written underneath as her superhero name.
17.Throughout The Lord of the Rings trilogy, Frodo references the One Ring "getting heavier" as they approach Mordor. Once inside Mount Doom, many sores and bruises are visible on his neck, referencing how heavy (literally) this burden was to bear.