Hemsley, Jr. was not from Wisconsin but rather born in Bridgeport, Connecticut. After graduating with an M.F.A. from Yale School of Drama in 1960, he immersed himself in the theatre world as a production manager, technical director, and expert in lighting design. His professions took him all over the United States from a summer theater and restaurant in Rhode Island to the Dallas Civic Opera in Texas and eventually to a natural limestone cave in Blue Mounds, Wisconsin.
Throughout his travels, Hemsley, Jr. was a guest lecturer to many universities including Yale, Adelphi, Temple, Stanford, Syracuse, among others. He came to Wisconsin to visit a faculty member at the University of Wisconsin-Madison from 1969 to 1970. Hemsley, Jr. ultimately accepted a faculty position as Professor of Theater Lighting and Production Management at the college. Like most professors in an artistic field, he continued to travel across the world sharing his talents. According to sources, he often would bring his students along to production projects in New York to provide them real-life experience.
Hemsley, Jr. was nationally and internationally recognized. He was the production supervisor and lighting director of the New York City Opera, and also did lighting for Martha Graham Dance Company, The Metropolitan Opera, American Ballet Theater, Bolshoi Ballet, Stuttgart Ballet, National Ballet of Cuba, and numerous regional ballet, opera, and theater companies, including Broadway plays and musicals.