Blythe studied acting and got her degree from Bard College and began her career in Boston theater companies. By 25, she won the Theater World Award for her work in 'Moliere' 's "The Miser" at Lincoln Center. She also won the 1970 Tony award for her role in "Butterflies Are Free". She made her film premiere in the same year in the television production of Dr. Cook's Garden (1971) (TV). For 25 years, she has been a regular performer at the Williamstown Summer Theater Festival. She has also been nominated for Tonys for performances in "A Streetcar Named Desire" and "Betrayal". Married to director Bruce Paltrow, she is the mother of two acting children Gwyneth Paltrow and Jake Paltrow.