Isabel Bigley, who died Saturday at 80, was the sprightly starlet who created the role of Sarah Brown in “Guys and Dolls.” She was thought to be the last surviving member of a cast that included Robert Alda, who co-starred as Sky Masterson.

Already well known as an actress on Broadway and in London’s West End, Bigley won the 1951 Tony for best actress in a musical, in part for her rendition of “If I Were a Bell,” the song in which the ingénue tries liquor for the first time, then sings of her feelings for Masterson: “Ask me, how do I feel / Ask me now that we’re cozy and clinging / Well, sir, all I can say is if I were a bell, I’d be ringing.”

Walter Winchell called her “the most refreshing newcomer to hit B’way since Mary Martin scaled the heights by chanting ‘My Heart Belongs to Daddy.'”

After 70 weeks with “Guys and Dolls,” Bigley left in 1953 to star in a new Rodgers and Hammerstein musical, “Me and Juliet,” in a part written especially for her. Bigley received huzzahs for her debut of the lilting “No Other Love,” later a hit for Perry Como, but the musical got mediocre reviews.

Sadly for musical theater, Bigley had already discovered her other love, Larry Barnett, vice president of the Music Corporation of America and not coincidentally her agent (as well as Ronald Reagan’s). It was national news when the pair wed in 1953.

She stayed with “Me and Juliet” until it closed in April 1954, then left the theater behind.

Bigley grew up in the Bronx and attended Walton High School, where her music teacher arranged for her to receive a scholarship to Juilliard.

At her father’s insistence, Bigley took secretarial courses while studying singing and eventually worked for a Wall Street firm while auditioning for shows. One day in 1946, she took a long lunch and hopped on a subway to the St. James Theater on 44th Street for an audition to be a chorus replacement in the original production of “Oklahoma!” She did so well that she never returned to her job. When Parade magazine profiled her a few years later, she confided that she still kept her diary in shorthand.

In 1946, Bigley joined the chorus of the original production of “Oklahoma!” and after five months transferred to the London production as understudy in the lead role of Laurey. She soon took over the part, opposite Howard Keel as Curly.

Bigley was popular in London and performed in a BBC musical, “Rosalinda.” In 1950, she starred in a British weekly television show, “Café Continental,” which was broadcast nationally in America. Howard Hughes gave her a screen test, and the producers of Frank Loesser’s “Guys and Dolls” flew to London and hired her to play Sarah Brown.

Through the 1950s, Bigley appeared frequently on television, including a regular spot with Ed Sullivan and also occasionally on the “Colgate Comedy Hour” with Kukla, Fran, and Ollie. In 1958, she retired to Rye to raise a family.

She and her husband later moved to Los Angeles and became benefactors of several cultural organizations, including the McCallum Theater in Palm Desert, Calif., where Bigley sat on the board of directors.

Her husband survives her, as do her six children, 16 grandchildren, and four great-grandchildren.