It marked the film debut of William Hurt and Drew Barrymore. Chayefsky was credited as a screenwriter for the film using the pseudonym Sidney Aaron, his actual first and middle names.
The film score was composed by John Corigliano (with Christopher Keene conducting). The film was nominated for the Academy Award for Best Sound Mixing.
Edward Jessup is an abnormal psychologist who, while studying schizophrenia, begins to think that "our other states of consciousness are as real as our waking states." Jessup begins experimenting with sensory deprivation using a flotation tank, aided by two like-minded researchers, Parrish and Rosenberg. At a faculty party he meets fellow "whiz kid" and biological anthropologist Emily, and the two eventually marry.
The film skips ahead seven years. Eddie and Emily have two daughters, are on the brink of divorce, and reunite with the couple who first introduced them. When Edward hears of a Mexican tribe that experiences shared illusion states, he travels to Mexico to participate in what is apparently an Ayahuasca Ceremony. During the walk into the bush his guide states that the indigenous tribe they are meeting works with Amanita muscaria which they are collecting for next year's ceremonies. The tribe refer to one of the ingredients of the mixture they use as "First Flower." An indigenous elder is seen with Banisteriopsis caapi root in his hand prior to cutting Jessup's hand, adding blood to the mixture he is preparing. Immediately after consuming the mixture, Edward experiences bizarre, intense hallucinations. He returns to the U.S. with a tincture and continues taking it to trigger his ability to experience altered states of consciousness.
When toxic concentrations of the substance make increased dosage dangerous, Jessup returns to sensory deprivation, believing it will enhance the effects of the substance at his current dose. Repairing a disused tank in a medical school, Jessup uses it to experience a series of increasingly drastic visions, including one of early hominids. Monitored by his colleagues, Jessup insists that his visions have "externalized". Emerging from the tank, his mouth bloody, frantically writing notes because he is unable to speak, Jessup insists on his being x-rayed before he "reconstitutes." A radiologist inspecting Jessup's X-rays says that they belong to a gorilla.
In later experiments, Jessup experiences actual, physical biological devolution. At one stage he emerges from the isolation tank as a feral and curiously small-statured, light-skinned Primitive Man, going on a rampage before returning to his natural form. Despite the concern of colleagues, Jessup stubbornly continues.
In the ultimate experiment, Edward experiences a more profound regression, transforming into an amorphous mass of conscious, primordial matter. An energy wave released from the experiment stuns Jessup's colleagues, and destroys Jessup's tank. Emily arrives to find a swirling maelstrom where the tank had been. Emily searches the vortex for Jessup, finding him as he is on the brink of becoming a non-physical form of proto-consciousness and possibly disappearing from our version of reality altogether.
His friends bring Edward home, hoping that the transformations will end. Watched over by Emily, Jessup begins to regress again, the transformations no longer requiring intake of "first flower" or sensory deprivation. Urging Jessup to fight the change, Emily grabs his hand, immediately being enveloped by the primordial energy emanating from Jessup. The sight of Jessup's wife, apparently being consumed by the energy, stirs the human consciousness in Jessup's devolving form. He fights the transformation and returns to his human form. In the final scene, Jessup embraces Emily, and his love returns her to normal.William Hurt as Dr. Edward "Eddie" Jessup
Blair Brown as Emily Jessup
Bob Balaban as Arthur Rosenberg
Charles Haid as Mason Parrish
Thaao Penghlis as Eduardo Echeverria
Drew Barrymore as Margaret Jessup
Megan Jeffers as Grace Jessup
Miguel Godreau as Primal man
Dori Brenner as Sylvia Rosenberg
Peter Brandon as Alan Hobart
Charles White-Eagle as The Brujo
John Larroquette as X-Ray technician
George Gaynes as Dr. Wissenschaft
Jack Murdock as Hector Orteco
The film's original director was Arthur Penn, who resigned after a dispute with Chayefsky according to Mad As Hell, a 2014 book by Dave Itzkoff. Special effects expert John Dykstra was replaced by Bran Ferren, who is credited for Special Visual Effects in the front titles, and created the VFX actually used in the film. The film was produced originally at Columbia Pictures, which would later end its participation with it, before Warner Bros. bought the rights. Chayefsky later withdrew his name from the project; film critic Janet Maslin, in her review of the film, thought it "easy to guess why":
It's easy to guess why he and Mr. Russell didn't see eye to eye. The direction, without being mocking or campy, treats outlandish material so matter-of-factly that it often has a facetious ring. The screenplay, on the other hand, cries out to be taken seriously, as it addresses, with no particular sagacity, the death of God and the origins of man.
Film critic Richard Corliss attributed Chayefsky's disavowal of the film to distress over "the intensity of the performances and the headlong pace at which the actors read his dialogue."
Russell maintained that he changed almost nothing in Chayefsky's script, and called the writer "impossible to please."
Itzkoff's book chronicles the making of Altered States and claims that Russell, objecting to Chayefsky's interference, had the writer banned from the set. Chayefsky reportedly tried to have Russell removed as director, but by then the film was already well under way, and the studio already had replaced one director (Penn). Chayefsky elected to remove his name from the credits, even though he was paid $1 million for it and it was his first screenplay after winning an Academy Award for Network.
Selected premiere engagements of Altered States were presented in Megasound, a surround sound system similar to Sensurround.
Rotten Tomatoes gave the film a rating of 86% "Fresh" and a consensus that states "Extraordinarily daring for a Hollywood film, Altered States attacks the viewer with its inventive, aggressive mix of muddled sound effects and visual pyrotechnics." Janet Maslin of The New York Times termed the film a "methodically paced fireworks display, exploding into delirious special-effects sequences at regular intervals, and maintaining an eerie calm the rest of the time. If it is not wholly visionary at every juncture, it is at least dependably — even exhilaratingly — bizarre. Its strangeness, which borders cheerfully on the ridiculous, is its most enjoyable feature." She also called it "in fine shape as long as it revels in its own craziness, making no claims on the viewer's reason. But when it asks you to believe that what you're watching may really be happening, and to wonder what it means, it is asking far too much. By the time it begins straining for an ending both happy and hysterical, it has lost all of its mystery, and most of its magic."
Richard Corliss began his review of the film thus:
This one has everything: sex, violence, comedy, thrills, tenderness. It's an anthology and apotheosis of American pop movies: Frankenstein
, Murders in the Rue Morgue
, The Nutty Professor
, Love Story
. It opens at fever pitch and then starts soaring—into genetic fantasy, into a precognitive dream of delirium and delight. Madness is its subject and substance, style and spirit. The film changes tone, even form, with its hero's every new mood and mutation. It expands and contracts with his mind until both almost crack. It keeps threatening to go bonkers, then makes good on its threat, and still remains as lucid as an aerialist on a high wire. It moves with the loping energy of a crafty psychopath, or of film makers gripped with the potential of blowing the moviegoer's mind out through his eyes and ears. Ladies and gentlemen, welcome to Altered States
Corliss calls the film a "dazzling piece of science fiction"; he recognizes the film's dialogue as clearly Chayefsky's, with characters that are "endlessly reflective and articulate, spitting out litanies of adjectives, geysers of abstract nouns, chemical chains of relative clauses", dialogue that's a "welcome antidote to all those recent...movies in which brutal characters speak only words of one syllable and four letters." But the film is ultimately Russell's, who inherited a "cast of unknowns" chosen by its original director and "gets an erotic, neurotic charge from the talking-heads scenes that recall Penn at his best."
Pauline Kael, on the other hand, wrote that the "grotesquely inspired" combination of "Russell, with his show-biz-Catholic glitz mysticism, and Chayefsky, with his show-biz-Jewish ponderousness" results in an "aggressively silly picture" that "isn't really enjoyable."
John C. Lilly liked the film, and noted the following in an Omni magazine interview published in January 1983:
The scene in which the scientist becomes cosmic energy and his wife grabs him and brings him back to human form is straight out of my Dyadic Cyclone
(1976)...As for the scientist's regression into an ape-like being, the late Dr. Craig Enright, who started me on K (ketamine) while taking a trip with me here by the isolation tank, suddenly "became" a chimp, jumping up and down and hollering for twenty-five minutes. Watching him, I was frightened. I asked him later, "Where the hell were you?" He said, "I became a pre-hominid, and I was in a tree. A leopard was trying to get me. So I was trying to scare him away." The manuscript of The Scientist
(1978) was in the hands of Bantam, the publishers. The head of Bantam called and said, "Paddy Chayefsky would like to read your manuscript. Will you give him your permission?" I said, "Only if he calls me and asks permission." He didn't call. But he probably read the manuscript.
In Ready for My Close-Up!: Great Movie Speeches (2007), screenwriter Denny Martin Flinn called Chayefsky's screenplay "brilliant" and selected Emily's speech as "Chayefsky's last great take on life and love."
The film was nominated for two Academy Awards:Academy Award for Best Sound - Arthur Piantadosi, Les Fresholtz, Michael Minkler and Willie D. Burton
Academy Award for Best Original Score - John Corigliano