Film facts

1. Charlie Chaplin solicited help from Granville Redmond, a deaf friend, to teach him pantomime techniques he later used in his silent films.

1. The film Memento is lauded by medical experts for its accurate portrayal of anterograde amnesia and is considered "close to a perfect exploration of the neurobiology of memory."

1. The people who falsely claimed the copyright on "Happy Birthday to You" made $2 million a year for decades until a court ruled the song to be public domain in 2016.

1. In "Apocalypse Now," the opening shot was reconstructed from scraps of film that were otherwise destined for the landfill. By sheer luck, Coppola stumbled upon it after shooting 1.5 million feet of film. Coppola also instructed the editor to use "The End" by The Doors since he found the idea of opening a film with that song to be amusing.

1. In Toy Story 4 (2019), a closer look at Buzz Lightyear shows that his stickers are slowly starting to peel away.

After we started digging, so many Wizard of Oz secrets blew our minds. Here are 25+ interesting facts you might not have known about the film.