This is Spinal Tap (1984)

82 min - Comedy, Music
Spinal Tap, the world's loudest band, is chronicled by hack documentarian Marty DeBergi on what proves to be a fateful tour.
Director: Rob Reiner
Writers: Christopher Guest, Michael McKean
Stars: Rob Reiner, Michael McKean, Christopher Guest, Kimberly Stringer
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The Na'vi language was created entirely from scratch by linguist Paul Frommer, who was hired by James Cameron to construct a language that was easily pronounceable by the actors, but lacking any resemblance or influence from any single human language. Around 500 words were created.
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