I have serious late fees on my video account because I just didn't want to give this movie back. It is stunning that a film with special effects this beautiful and fitting was made in 1980, but that wasn't why I kept watching it over and over.
I tend to be incredibly critical of most Sci-Fi movies on technical grounds (spoiled by a physics degree and 5 years of philosophy graduate courses) so I was stunned by the tightness of this movie. Obviously it's fiction and at some point goes off the deep end scientifically, but like the best X-files episodes (but much better), it leaves you impressed by how well it justifies its leaps of fancy.
Movie premise (not a spoiler):
Jessup is a young hotshot professor at the Harvard Medical School in the early 70's. His original work focused on the neurological deformities among schizophrenics. Allegedly (and this IS true) only advanced schizophrenia is visible in the structure of the brain--early schizophrenia is not, though people who suffer from it still experience similar mental problems. His original research focused on explaining why this is the case (not featured in the movie; left implied). Apparently, there are no models to explain how the neurological deformity associated with schizophrenia is caused (maybe false, but not stupid) so Jessup starts taking seriously the idea that the MENTAL disorder considered to be early schizophrenia actually CAUSES the characteristic change in structure. This is a pretty wild conjecture, I agree. Remember though that most movies ask you to make much bigger leaps. What's classy about "Altered States" is that it correctly treats this as a wild conjecture and Jessup receives quite hard time from his colleagues for thinking something this flaky. In an attempt to discover the physical mechanism by which thoughts affect physical structure, Jessup begins experimenting with altered states of consciousness in a sensory deprivation tank, later in conjunction with processed hallucinogens from the Amanita Muscaria mushroom. Well, it's no spoiler to say that he finds evidence for his theory that mental states can have an effect on morphological structure. By warping his mind enough, he undergoes several of these changes himself.
Another somewhat questionable theory the viewer is asked to accept is the idea that memories can be written in DNA and inherited. This amounts to something like innate knowledge. Again, people believe crazier things, and this isn't too much of a stretch for fiction. It's certainly true that instincts are inherited and innate: for example, babies "remember" how and when to suck (as do most recent movies of the Hollywood pedigree). Some research shows that fear of snakes may be innate, and if so, it must be encoded somewhere in our DNA. Well, according to the movie, some of these encoded memories are latent and not retrievable to the modern Homo Sapiens (no longer useful for our survival). However, some altered states of consciousness can cause us to conjure up these vestigial memories. Well, a little cooky for the New England Journal of Medicine, but too crazy to accept as a movie premise? Hardly!
This is the first movie of its kind since "2001" where a savvy viewer doesn't have to slap her hand over her eyes and say "come on, that is soo implausible!"
What's more, this solid science fiction premise is embedded in a script with excellent dialogue and three dimensional characters. William Hurt does an excellent job. I have to agree with other reviewers that the ending was a little cheesy, but it didn't bother me when I watched the movie. By the end the film generates so much good will you are able to forgive just about anything, and it's really not so bad.
SPOILERS--stop reading here and rentbuy the masterpiece of a movie NOW if you still haven't! That's an order!
In retrospect, I think the movie would have worked fine if Jessup didn't actually grow hair, shrink and blow up the tank with his transformation. Where did all that energy come from? His brain waves? I would have been happier if the transformation happened only on a cellular level (explanation: what we think of as "junk" DNA is actually simian DNA and it suddenly becomes active through the effect of his thoughts, producing both simian proteins and neurotransmitters; brain begins working in a characteristically simian way, higher brain functions turn off, Jessup goes nuts...) Anyway, the movie only needed a tiny bit more tinkering before it became totally responsible scientifically. All the same, the scientist are portrayed realistically, not like the caricatures that most Hollywood movies draw of them. I wish this sort of movie would get made these days. Instead we have to live with the gaping plotcoherency holes in AI, the Matrix and worse! Altered States makes new Sci-Fi look like it was made by a bunch of know-nothing hacks.
Review by spazmodeus from the Internet Movie Database.