Behind the iconic jazz orchestras, vocalists, and stage productions of the Swing Era lay the talents of popular music's unsung heroes: the arrangers. John Wriggle takes you behind the scenes of New York City's vibrant entertainment industry of the 1930s and 1940s to uncover the lives and work of jazz arrangers, both black and white, who left an indelible mark on American music and culture. Blue Rhythm Fantasy traces the extraordinary career of arranger Chappie Willet--a collaborator of Louis Armstrong, Cab Calloway, Duke Ellington, Gene Krupa, and many others--to revisit legendary Swing Era venues and performers from Harlem to Times Square. Wriggle's insightful music analyses of big band arranging techniques explore representations of cultural modernism, discourses on art and commercialism, conceptions of race and cultural identity, music industry marketing strategies, and stage entertainment variety genres. Drawing on archives, obscure recordings, untapped sources in the African American press, and interviews with participants, Blue Rhythm Fantasy is a long-overdue study of the arranger during this dynamic era of American music history.