Moore made her stage debut starring as Casilda in the Gilbert and Sullivan hit, "The Gondoliers", in 1889 at the age of 17 and stayed with the company for two years. She then starred in a variety of West End theatre plays and musical pieces over the next two years, joining the George Edwardes company to create the ingénue role of Rose Brierly in the hit Edwardian musical comedy "A Gaiety Girl" in 1893. After touring with Edwardes's company in musicals, she returned to England and light opera later playing the role of Scent of Lilies in "The Rose of Persia" (1899) and starring in "Florodora" (1900–01) and "My Lady Molly" (1903), among other West End shows.