Jennie (Susan Strasberg) travels to San Francisco to locate her hippie brother Steve (Bruce Dern). She meets Stoney (Jack Nicholson) in a coffeehouse and he helps her look for Steve, who Stoney has seen in his various attempts to start a rock & roll band.
Stoney and his pals transform the square girl into a swinging hippie chick, complete with a mod miniskirt. Along with their buddy Dave (Dean Stockwell), they search for Steve amidst the psychedelic splendor of the Haight-Ashbury hippie haunts.
Dave is killed by a car when he wanders around in an STP-induced stupor. LSD, marijuana, and the good and the bad sides of hippie life are illustrated with non-judgmental accuracy.
The soundtrack of the movie is a musical gem, complete with the international smash Incense and Peppermints by the Strawberry Alarm Clock. (The group reached the top of the charts with the song in October 1967.) Also on hand are the Seeds, although they don't get to perform their best-known song, Pushin' to Hard. (Seeds lead singer Sky Saxon would gain as much notoriety as an acid casualty as he would from his musical ability.) Also adding music are the Storybook and Cryque Boenzee.
The latter group contained Rusty Young and George Grantham, who would join with former Buffalo Springfield members Richie Furay and Jim Messina from the legendary, long-lived country-rock band Poco. This time-capsulized gem was produced by Dick Clark, the world's oldest teenager.