Born in Hutchinson, Kansas, Corsaut was the daughter of Jesse Harrison and Opal J. Corsaut. She majored in drama at Northwestern University and studied acting with Lee Strasberg. During her junior year, Corsaut dropped out to pursue a career in acting, although during the run of The Andy Griffith Show, Corsaut took courses at UCLA with plans to earn her degree. She began her acting career in New York City in the mid-1950s. In 1958, Corsaut and Steve McQueen made their film debuts in the independent cult horror filmThe Blob. On television, in 1961-1962, she portrayed Irma Howell on the CBSsitcomMrs. G. Goes to College. Corsaut first appeared on the long-running Griffith show in 1963 as schoolteacher Helen Crump, who later became the Mayberry sheriff's wife on the first episode of the spinoff Mayberry R.F.D. In 1965 she was also cast as Kathy McLennan, the young widow of a rancher, in the episode "Paid in Full" on the syndicatedWesternanthology seriesDeath Valley Days. Corsaut later had a continuing role as policeman Bumper Morgan's pawn-shop-owner friend on the 1975-1976 series The Blue Knight. In the series Adam-12, Corsaut portrayed Officer Pete Malloy's girlfriend Judy. She had a supporting role too as Head Nurse Bradley in the 1980s sitcom House Calls, and she appeared in several episodes of Matlock with star Andy Griffith. In addition, Corsaut played the role of nurse Jesse Brewer in 1977 on the long-running ABC soap operaGeneral Hospital when long-time portrayer Emily McLaughlin was too ill to work. She returned to the role of Helen Crump in the reunion shows Return to Mayberry in 1986 and The Andy Griffith Show Reunion in 1993. As a writer, she coauthored The Mystery Reader's Quiz Book.
Corsaut never married or had any children. According to the 2015 book Andy & Don: The Making of a Friendship and a Classic American TV Show, she and Andy Griffith, who was married at the time, had an affair while working together on The Andy Griffith Show. On November 6, 1995, Corsaut died of cancer in Los Angeles, California, just three days after her 62nd birthday. A Catholic, she was interred at Valhalla Memorial Park Cemetery in nearby North Hollywood.
