Costello began performing at several locales, including the Copacabana Club. to appear on the Broadway stage; however
Lupe Vélez had three Broadway credits before Costello's 1939 Broadway debut. She became the first Puerto Rican vedette to co-star in Broadway. In 1945, Costello appeared in
The Bullfighters as "Conchita". She married director Jacinto Campos. Besides New York, both would appear at Florida and the Hollywood Trocadero, before their marriage ended in divorce. In 1951 she replaced
Juanita Hall in the role of Bloody Mary in the original Broadway production of
South Pacific. Despite being involved in a train crash while touring, she performed in this musical for five years. During the 1950s, she also recorded productions such as Eliseo Grenet's
El Maraquero. She also made appearances in other mediums, such as
The Ed Sullivan Show. In 1953, Costello made an appearance as Ameena Horn in
Miss Sadie Thompson. During the 1960s, Costello performed in Puerto Rico and made appearances in
the television industry of Puerto Rico. Afterwards, Costello retired and decided to distance herself from the spotlight, declining awards and offers to leave retirement. ==Later life==