Halman began her professional singing career on tour with the Carl Rosa Opera Company. After further experience in concert work and teaching, she joined the D'Oyly Carte Opera Company as a chorister in 1937. She soon was playing the role of Inez in "The Gondoliers" and understudying the larger contralto roles. From 1939 to 1951, she was the company's principal contralto. She and her husband then toured in Gilbert and Sullivan productions in America. They retired to Penrith, Cumbria, England, where they became involved with amateur operatic societies. She recorded eight of her roles with D'Oyly Carte.