The design of the Na’vi was one of the most striking parts of James Cameron’s Avatar, an entire race of people with their own look and language. But the look of the Na’vi didn’t come from Cameron or his talented team of artists. They actually came from his mom. Yes, the design of the Na’vi came from a dream James Cameron’s mother had and relayed to her son. That’s just one of the facts packed into the latest episode of You Think You Know Movies, which takes you on an unexpected journey behind the scenes of Avatar !

Long before he was Star-Lord, Chris Pratt auditioned for the role of Jake Sully in Avatar when James Cameron was looking for an unknown to star in the film. Pratt didn’t get the role and said his particularly tough audition almost caused him to quit acting. “They said they want somebody that has ‘that thing,’ that ‘It factor’ … I walked into that room knowing that I did not have that thing, and I walked out thinking I would never have that thing.” That same year, Pratt would get cast as Andy Dwyer on Parks and Recreation and the rest is history.

You Think You Know Movies is a ScreenCrush original series that dives deep into the cinematic worlds of your favorite movies and freeze frames a few tidbits you might not have known. We’ve already tackled Star Wars, The Avengers, and Spider-Man, but now it’s time to get ready for some Avatar facts.

Watch more installments of You Think You Know Movies below, and let us know what movies we should cover next.

Check Out 100 Movie Facts You Might Not Know

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