The best part about rewatching movies is catching hidden references you didn’t see the first time around.
These hidden references are sometimes known as Easter eggs. They can be anything from an inside joke on set to a shout-out to another film.
From “Star Wars” to “The Godfather,” let’s go on a scavenger hunt for some of the best hidden references in your favourite films.
Most movie Easter eggs subtly reference another piece of pop culture. For example, 1982's 'Tron' hid the arcade favourite 'Pac-Man' on a map within the film's video-game-like grid.
They can also be used by directors to acknowledge one another. This was the case when Steven Spielberg's 1981 'Raiders of the Lost Ark' included a hieroglyphic of R2-D2 and C-3PO from George Lucas' 1977 'Star Wars.'
Spielberg did it again when he named a club in 1984's 'Indiana Jones and the Temple of Doom' after the Jedi master Obi-Wan Kenobi.
Lucas returned the favour in 1999's 'Star Wars Episode I: The Phantom Menace' when he included aliens from Spielberg's 1982 'E.T. the Extra-Terrestrial' in the galactic senate.
Hidden 'Star Wars' references pop up in other films, too. Avid 'Star Wars' fan and 'Episode VII' director J.J. Abrams had R2-D2 appear in 2009's 'Star Trek' as a piece of debris floating through space.
Easter eggs are also hidden cameos, such as Glenn Close dressing up as a bearded male pirate who was tortured by Captain Hook in 1991's 'Hook.'
Hidden references can even be seen as symbolism or foreshadowing. For example, many fans see oranges in 1972's 'Godfather' as a symbol of death.
The same concept was more deliberate in 2006's 'Departed.' Martin Scorsese paid homage to old gangster movies by sprinkling X's all over the film to express impending doom.
'Jurassic Park' (1993) has a symbolic hidden reference. When the helicopter lands on the island, Dr. Grant ties two female ends of a seat belt together. Fans see this as a metaphor for the DNA splicing that lets the dinosaurs reproduce in the film (even though they're all female).
Sometimes Easter eggs can give a brief nod to a film's storyline. When Marty McFly travels back in time in 1985's 'Back to the Future' he runs over a pine tree. When he returns to the future, there's a name change to the mall named after the pines.
Easter eggs also reference films that have yet to come. This was done when the shield of future Avenger Captain America showed up in Tony Stark's workshop in 2008's 'Iron Man.'
They can even accidentally predict films that don't exist as 2007's 'I Am Legend' did when it had a billboard for a Batman-Superman movie hanging in its dystopian Times Square.
Hidden movie references aren't new, however. Director Alfred Hitchcock used to sneak himself into many of his films. He did so in his 1944 film 'Lifeboat' (which took place on a boat lost at sea) by sneaking himself into a newspaper ad.
The original 1968 'Planet of the Apes' also snuck in a hidden reference by having three apes 'see no evil, hear no evil, and say no evil,' thus reenacting the 'Three Wise Monkeys' pose.
Some Easter eggs have become so popular that fans look forward to them. Any time a 'Star Wars' movie comes out fans wait to see which character says some variation of 'I have a bad feeling about this' -- a line said in every film of the series.
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