In Jimmy Dean, she was the oft-pregnant Edna Louise, a hapless member of a James Dean fan club that also included characters played by Karen Black, Cher and Sandy Dennis. All of the actresses graduated from the 1982 stage production to Altman's later film. Altman had previously cast her in "A Wedding" (1978) and "A Perfect Couple" (1979) opposite Paul Dooley, a film about the romance between a gypsy-like rock singer and a divorced older businessman. The part had originally been written for Sandy Dennis. But Dennis was a cat lover, and Dooley was allergic to the felines she would bring to script readings. Her last film role was a small part in Martin Scorcese's "The King of Comedy." Ms. Heflin was born into an artistic family. Her father was the film actor Van Heflin, and her mother was theatre producer Julia Heflin. An aunt, Frances Heflin, was also an actress.

In 1967, Ms. Heflin was part of the chorus of a City Center revival of the Lerner and Loewe musical Brigadoon. When the actress playing the role of Meg fell sick, she assumed the part. She made her Broadway debut in Fiddler on the Roof, and appeared in two of the seminal rock musicals of the late '60s and early '70s, playing the pregnant waif Sheila in Hair and Mary Magdalene in Jesus Christ Superstar.