Jack Nicholson as Robert Eroica Dupea

Karen Black as Rayette Dipesto

Susan Anspach as Catherine Van Oost

Lois Smith as Partita Dupea

Ralph Waite as Carl Fidelio Dupea

Billy Green Bush as Elton

Irene Dailey as Samia Glavia

Toni Basil as Terry Grouse

Lorna Thayer as Waitress

Richard Stahl as Recording Engineer

Helena Kallianiotes as Palm Apodaca

William Challee as Nicholas Dupea

John P. Ryan as Spicer

Fannie Flagg as Stoney

Marlena MacGuire as Twinky

Sally Struthers as Betty

Clay Greenbush as Baby (uncredited)

Bob Rafelson as Man in Elevator (uncredited)