In 1938 he started arranging music for theater in Fort Worth, Texas. Returning to New York to work on "Billy Rose's Aquacade" for the World's Fair, he came to the attention of Max Dreyfus who ran the in-demand theater orchestration department at Chappell Music. In just two weeks his hard-working team could orchestrate the average musicomedy for the price of $6,000. Dreyfus signed Royal as a house orchestrator and in 1939 he moved into the same building with Robert Russell Bennett, Don Walker and Hans Spialek.