Three young women — Kelly MacNamara, Casey Anderson, and Petronella “Pet” Danforth — perform in a rock band, the Kelly Affair, managed by Harris Allsworth, Kelly’s boyfriend. The four travel to Los Angeles to find Kelly’s estranged aunt, Susan Lake, heiress to a family fortune. After Susan promises Kelly a third of her inheritance, Porter Hall, her sleazy financial advisor, discredits Kelly as a “hippie” to dissuade Susan from dividing the fortune he secretly wants to embezzle.
Undeterred, Susan introduces the Kelly Affair to a flamboyant, well-connected rock producer, Ronnie “Z-Man” Barzell, who coaxes them into an impromptu performance at one of his outrageous parties (after a set by real-life band Strawberry Alarm Clock). The band is so well-received that Z-Man becomes their svengali manager, changing their name to the Carrie Nations and starting a long-simmering feud with Harris.
Kelly drifts away from Harris and dates Lance Rocke, a high-priced gigolo, who has his own designs on her inheritance. After losing Kelly, Harris is seduced by the sexually aggressive porn star Ashley St. Ives. She soon tires of his conventional nature and waning libido due to increasing drug and alcohol intake. Harris’s further descent into drug and alcohol use leads to a fistfight with Lance and a one-night stand with Casey which results in pregnancy. Kelly ends her affair with Lance after he severely beats Harris.
Casey, distraught at getting pregnant and wary of men’s foibles, has a lesbian affair with clothes designer Roxanne, who pressures her to have an abortion. Petronella has a seemingly enchanted romance with law student Emerson Thorne after a meet cute at one of Z-Man’s parties. Their fairy-tale romance frays when Pet sleeps with Randy Black, a violent prize fighter who beats up Emerson and tries to run him down with a car.
Porter offers Kelly $50,000 to relinquish any claim to Susan’s inheritance. When Kelly angrily rejects his offer at one of Z-Man’s parties, Susan learns of his underhanded ploy and severs her ties with him.
The Carrie Nations release several records despite constant touring and drug use. Upset at being pushed to the sidelines, Harris attempts suicide by leaping from the rafters of a sound stage during a television appearance by the band. Harris survives the fall but becomes paraplegic from his injuries.
Kelly devotes herself to caring for Harris and Emerson forgives Petronella for her infidelity. Casey and Roxanne share a tender romance and Susan Lake is reunited with her former fiancé, Baxter Wolfe. This idyllic existence ends when Z-Man invites Casey, Roxanne, and Lance to a psychedelic-fueled party at his house. After Z-Man tries to seduce Lance, who spurns him, he reveals that he has breasts and is a female in drag.[N 1] Z-Man goes on a murderous rampage: he beheads Lance with a sword, stabs his servant Otto to death, and shoots Roxanne and Casey, killing them.
Responding to a desperate phone call Casey made shortly before her death, Kelly, Harris, Pet, and Emerson arrive at Z-Man’s house to subdue him. Petronella is wounded in the melee, which ends in Z-Man’s death. Harris is able to move his feet, the start of his recovery from paralysis. Three couples — Kelly and Harris, Pet and Emerson, and Susan and Baxter — wed while Porter watches from outside the courthouse window.