Dupree made her acting debut in a touring company under John A. Stevens in 1887. The next year, she made a big impression in a small role in William Gillette's New York play Held by the Enemy. Subsequently, she received a number of important supporting roles, working with the likes of Richard Mansfield, Stuart Robson, and Nat Goodwin. She finally landed a starring role in 1900 in Women and Wine. Other leading roles followed, including in The Climbers (1901), A Rose o' Plymouth-town (1902), Heidelberg (1902), The Music Master (1904), and The Road to Yesterday (1906).
On November 8, 1896, it was announced that she would marry Major William H. Langley, a reputed millionaire, at the end of the season. At the time, she was described as a "handsome blonde, and the possessor of a magnificent head of curly hair."