Mariclare Costello, a versatile actor known for her role as the compassionate schoolteacher Rosemary Hunter on The Waltons and for her striking performance in the 1971 cult horror film Let’s Scare Jessica to Death, passed away on Friday, April 17, in Brooklyn. She was 90 years old, her family confirmed.
Costello built a rich and varied career across stage, film, and television. She appeared in nine Broadway productions during the 1960s and was deeply rooted in the theater world.
A graduate of Catholic University, where she earned a master’s degree in theater and education, she later became an original member of the Lincoln Center Repertory Company and a lifetime member of The Actors Studio.
Born on February 3, 1936, in Peoria, Illinois, Costello moved to New York City after completing her studies and quickly established herself on both Off-Broadway and Broadway stages.
Her Broadway debut came in 1964 in Arthur Miller’s After the Fall, where she performed alongside Jason Robards.
She went on to appear in several notable productions, including Tartuffe, Danton’s Death, The Country Wife, Lovers and Other Strangers, A Patriot for Me, and Harvey, the latter featuring James Stewart and Helen Hayes.