Set in the distant future, the film chronicles the conflict between rival noble families as they battle for control of the extremely harsh desert planet Arrakis, also known as "Dune". The planet is the only source of the drug melange—also called "the spice"—which allows prescience and is vital to space travel, making it the most essential and valuable commodity in the universe.

References:
https://en.wikipedia.org/wiki/Dune_(1984_film)