Must-see movies are futuristic classics that shouldn't be missed. Of course, not every must-see is perfect. That's why we've rated them 1-5 on the patented "crunchy goodness" scale.
Title: Altered States
Vitals: One of the last great LSD-inspired science fiction movies, Altered States follows the adventures of a scientist who takes some weird drugs, dips into a sensory-deprivation tank, and discovers he can de-evolve into Primitive Man and - even more dubiously - Primal Sludge.
Famous names: William Hurt
Crunchy goodness: 2
Ripoff: The thoroughly underrated Super Mario Bros. movie also plays with the idea of de-evolution. If you recall, the evil dinosaur leader (Dennis Hopper) in that flick defeats his enemies by using a de-evolution gun to turn them into moss.
Most painfully dated moment: The "bad trip" sequences with Satan permanently mark this as a movie from the era when Meatloaf and Black Sabbath ruled.
Memorable product tie-in: For reasons that only the Me Generation can understand, this movie created a brief craze for sensory deprivation tanks. For a few years, urbanites could find salons where they'd rent you time in one of these stinky black boxes full of salinated water, just so you could pretend you were one with the universe.