The plot begins in deep space, where a race of gelatinous creatures abandon their dying world. They make their way to Earth and land in San Francisco. They fall on plant leaves, assimilating them and forming small pods with pink flowers. Elizabeth Driscoll (Brooke Adams), an employee at the San Francisco Health Department, is one of several people who bring the flowers home.
The next morning, Elizabeth's boyfriend, Geoffrey Howell (Art Hindle), suddenly becomes distant, and she senses that something is wrong. Her colleague, health inspector Matthew Bennell (Donald Sutherland), suggests that she see his friend, psychiatrist Dr. David Kibner (Leonard Nimoy). While driving to Kibner's book party, they are accosted by a hysterical man (Kevin McCarthy). The man runs off, and is soon seen dead, surrounded by a crowd of emotionless onlookers. At the party, Matthew calls the police about the incident, and finds them strangely indifferent. An agitated party attendee starts declaring that her husband is not her real husband. Kibner works to reconcile them, and suggests that Elizabeth wants to believe that Geoffrey has changed because she is looking for an excuse to get out of their relationship.
Meanwhile, Matthew's friend Jack Bellicec (Jeff Goldblum), a struggling writer who owns a bathhouse with his wife Nancy (Veronica Cartwright) discovers a deformed body on one of the beds and calls Matthew to investigate. Noticing that the body (which is adult sized but lacks distinguishing characteristics) bears a slight resemblance to Jack, Matthew breaks into Elizabeth's home and finds a semi-formed double of her in the bedroom garden. He gets the sleeping Elizabeth to safety, but the duplicate body has disappeared by the time he returns with the police. The body at the bathhouse has also disappeared when Matthew returns there.
Matthew realizes that people are being replaced by extraterrestrial copies while they sleep. Matthew calls several state and federal agencies, but they all tell him not to worry. In addition, people who had earlier claimed that their loved ones had changed seem to have been converted as well, including (unbeknownst to him) Dr. Kibner.
That night, Matthew and his friends are nearly duplicated by the pods while they sleep. The pod people try to raid Matthew's house, but he and his friends are able to escape. During this, they discover that the pod people emit a shrill scream once they learn someone is still human among them.
Jack and Nancy create a diversion within a crowd of pursuing pod people to give Matthew and Elizabeth time to escape. Matthew and Elizabeth are chased across San Francisco. They are eventually found by the doubles of Jack and Dr. Kibner at the Health Department building. Kibner's double tells them that what the alien species is doing is purely for survival and that they are even doing humanity a favor by ridding them of emotion. Matthew and Elizabeth are injected with a sedative to make them sleep. However, having already taken a large dose of speed, the couple overpower them and escape the building.
In the stairwell, they find Nancy, who has learned to evade the pod people by hiding all emotion. Outside, Matthew and Elizabeth are exposed as human when Elizabeth screams after seeing a mutant dog with a man's face. They flee, and discover a giant warehouse at the docks where the pods are grown. After Matthew and Elizabeth profess their love for each other, Matthew goes out to investigate, only to discover a cargo ship being loaded with hundreds of pods.
Matthew returns to find that Elizabeth has fallen asleep. He tries to wake her, but her body crumbles to dust and her naked soulless double arises, telling him to embrace his fate and sleep. Matthew returns to the warehouse and sets it on fire, destroying many pods. He hides from the pod people under a pier, but they know he will have to fall asleep eventually.
The next morning, Matthew watches dozens of children being led into a theater to be replaced. At work he sees Elizabeth, but she is completely oblivious to him. While walking towards City Hall, he is spotted by Nancy, who has remained human. She calls to him, but he responds by pointing to her and emitting the piercing pod scream. Realizing that Matthew is now a pod person, Nancy, now the only human left in the city, screams in helpless terror.Donald Sutherland as Matthew Bennell
Brooke Adams as Elizabeth Driscoll
Leonard Nimoy as Dr. David Kibner
Jeff Goldblum as Jack Bellicec
Veronica Cartwright as Nancy Bellicec
Art Hindle as Dr. Geoffrey Howell, DDS
Don Siegel as Taxicab Driver
Kevin McCarthy as Running man
Wood Moy as Dry Cleaner owner
The film features a number of cameo appearances. Kevin McCarthy, who played Dr. Miles Bennell in the original Invasion of the Body Snatchers, makes a brief appearance as an old man frantically screaming "They're coming!" to passing cars on the street. Some reviewers have taken this scene to mean that the film is not a direct remake, but a sequel to the original, with the man on the street being an older version of Bennell, though McCarthy is simply credited as "Running man" in the film's credits. The original film's director, Don Siegel, appears as a taxi driver who pretends to drive Matthew and Elizabeth away from the city. Robert Duvall is also seen briefly as a silent priest on a swing set in the opening scene. Director Philip Kaufman appears in dual roles both as a man wearing a hat who bothers Sutherland's character in a phone booth, and the voice of one of the officials Sutherland's character speaks to on the phone. His wife, Rose Kaufman, has a small role at the book party as the woman who argues with Jeff Goldblum's character. Cinematographer Michael Chapman appears twice as a janitor in the health department.
The film score by Denny Zeitlin was released on Perseverance Records. Despite its popularity and critical praise, it is the only film score Zeitlin has composed.
The film featured a number of sound innovations. Bay-area sound designer Ben Burtt, who had just completed the groundbreaking sound effects for the 1977 Star Wars, created a number of "Special Sound Effects" for this film. The film's sound was mixed by Mark Berger at American Zoetrope in the four-channel Dolby Stereo process, which was not yet standard exhibition equipment in most theaters.
Philip Kaufman said of the casting of Leonard Nimoy, "Leonard had got typecast and this [film] was an attempt to break him out of that," referring to the similar perks that Dr. Kibner and his pod double had with Spock, the Star Trek character that Nimoy was most well known for. According to Kaufman, it was Mike Medavoy, then head of production at United Artists, who suggested the casting of Donald Sutherland. Sutherland's character had a similar curly hairstyle as that of another character he portrayed in Don't Look Now (1973). "They would have to set his hair with pink rollers every day," recalled co-star Veronica Cartwright. According to Zeitlin, Sutherland's character was originally written as an "avocational jazz player" early in development.
Invasion of the Body Snatchers earned nearly $25 million in box office revenue in the United States.
Invasion of the Body Snatchers is regarded as one of the greatest film remakes ever made. The New Yorker's Pauline Kael was a particular fan of the film, writing that it "may be the best film of its kind ever made". Variety wrote that it "validates the entire concept of remakes. This new version of Don Siegel's 1956 cult classic not only matches the original in horrific tone and effect, but exceeds it in both conception and execution." The New York Times' Janet Maslin wrote "The creepiness [Kaufman] generates is so crazily ubiquitous it becomes funny."
The film was not without its criticism. Roger Ebert wrote that it "was said to have something to do with Watergate and keeping tabs on those who are not like you,” and called Pauline Kael's praise for the movie "inexplicable", while Time magazine's Richard Schickel labeled its screenplay "laughably literal". Phil Hardy's Aurum Film Encyclopedia called Kaufman's direction "less sure" than the screenplay.
The film received a nomination from the Writers Guild of America for Best Drama Adapted from Another Medium. The film was also nominated for the Hugo Award for Best Dramatic Presentation. It was also recognized by the Academy of Science Fiction, Fantasy and Horror Films. Philip Kaufman won Best Director, and the film was nominated Best Science Fiction Film. Donald Sutherland, Brooke Adams and Leonard Nimoy received additional nominations for their performances.
Invasion of the Body Snatchers was released on DVD in the United States, Australia and many European countries. The film was released on Blu-ray Disc in the United States in 2010 and in the United Kingdom in 2013, and then remastered once more on Blu-ray in the United States and Canada in 2016.
The Chicago Film Critics Association named it the 59th scariest film ever made.