Altered States - Ken Russell - USA - (1980)

http://www.imdb.com/title/tt0080360/

Plot by Imdb:"A Harvard scientist conducts experiments on himself with a hallucinatory drug and an isolation chamber that may be causing him to regress genetically."

30 years old and still one of the best psychedelic movies of all-time, way better than the 70's hippies experiments, Ken Russell's Altered State stands as one of the weirdest experience on screen, an amazing mix between drugsploitation and SciFi. The cast is super solid, especially William Hurt who's carrying the whole movie on his shoulders; the hallucinations fx are old school but quite effective and add to the general feeling of strangeness. Ken Russell proves once again that he has no limits. He breaks every barriers of credibility and go all the way to a point where many would think the story is getting ludicrous. More than a drugsploitation movie, it's a very impressive exploration of a wild scientific theory. It could be related to the theory of Stanford Anthropology doctor Jeremy Narby in his book, "The cosmic Serpent", witch postulate that the ingestion of hallucinogenic plant Ayahuasca gives the Peruvian indigeneous  tribe Ashaninka some kind of molecular knowledge of life, especially the knowledge of the ADN structure of life, and helps them analyse the molecular properties of the forest around. In this movie, no ADN but a backward trip to our ancestors that ends up in the most peculiar way.

You definitively should try this movie, this is good medicine for the soul.

Trailer: