Benefit concert
Following the death of Bela Blau in the autumn of 1940, Ms Dillon returned to her first love, opera. She inaugurated The Deertrees Opera Company with the young Edwin McArthur (later replaced by Karl Kritz) as musical director and George Wells as scenic and lighting designer. The company consisted of some 12 to 15 young singers including Astrid Varnay, Phila Tharpe, and Elizabeth Caron and was a forerunner to the great opera-training programs to come to America some fifty years later. The Deertrees Opera Company continued into the summer of 1942 but with the United States in the war, after a Red Cross/U.S.O Benefit concert on August 31, the theatre went dark. In 1946, Ms. Dillon announced the re-opening of Deertrees Theatre for a "Summer Festival of Opera and Drama;" however, by mid-summer Ms. Dillon's health had deteriorated to the extent that she was unable to continue working and, on October 9, 1946, her brilliant career ended and the theatre closed.