15 Devilishly Clever Movie Secrets You Probably Missed

2. Every Pixar Movie Is Hidden In The Previous One

Pixar are famous for stuffing their movies chock-full of Easter eggs, references, and in-jokes, from the appearance of the Pizza Planet truck in almost all of Pixar's films, to the recurring use of the phrase "A113", which allures to the room number all of the Pixar Brain Trust took their intro to animation class in when they attended the California Institute of the Arts back in the '70s.

But one of the most remarkable and consistent Pixar Easter eggs is also one of the most clever: Every Pixar movie contains a reference to the Pixar movie that comes after it. Some of the references are more obvious than others - Nemo appears multiple times in Monsters Inc., most notably near the end when Boo tries to hand Sully a little clownfish doll to convince him to stay with her.

And the shadow of the dog who spooks Remi in an early scene in Ratatouille clearly belongs to Dug, one of the main characters from Pixar's Up. But some of the references are a little harder to spot - such as the kid reading a comic book about Mr. Incredible in Finding Nemo, or the Lotso bear doll tucked away in the corner of a room in a shot from Up that stays on screen for only a few seconds.

Brave featured an etching of Sully from Monster's University in the Witch's hut, and we only have to wait a few more months to see what references Monsters University has in store.