Collaboration is the lifeblood of the musical theater: Mozart and Da Ponte, Verdi and Boito, Strauss and Hofmannsthal. But posthumous collaboration has had to wait until the advent of the phonograph, motion pictures and the camcorder. Today the late George Gershwin can play Rhapsody in Blue with Michael Tilson Thomas, Natalie Cole can sing a duet with her deceased dad Nat King Cole--and composer Philip Glass can write a trilogy of operas with the French author, aesthete and movie director Jean Cocteau, dead since 1963.
This unlikely partnership between the modern American minimalist and the chain-smoking Gallic dandy has resulted in...