Peter Sellers stars as Harold Fine, a self-described square--a 35-year-old Los Angeles Lawyer who is not looking forward to middle age and his upcoming wedding. His life changes, however, when he falls in love with Nancy, a free-spirited, innocent, and beautiful young hippie. After Harold and his family enjoy some of her "groovy" brownies, he decides to "drop out" with her and become a hippie too. But can he return to his old life when he discovers that the hippie lifestyle is just a little too independent and irresponsible for his tastes?

Vince Lombardi High School keeps losing principals to nervous breakdowns because of the students' love of rock 'n' roll and their disregard of education. The putative leader of the students is Riff Randell, who loves the music of the Ramones. A new principal, the rock-music-hating Miss Evelyn Togar, is brought in and promises to put an end to the music craze. When Miss Togar and a group of parents attempt to burn a pile of rock records, the students take over the high school, joined by the Ramones, who are made honorary students. When the police are summoned and demand that the students evacuate the building, they do so, which leads to an explosive finale.

A couple's big dreams give way to a life full of unexpected sadness and unexpected joy.

A boardinghouse full of aspiring actresses and their ambitions, dreams and disappointments.