Written more than a century ago and initially regarded even by their creators as nothing more than light entertainment, the fourteen operas of Gilbert & Sullivan emerged over the course of the twentieth century as the world's most popular body of musical-theater works, ranking second only to Shakespeare in the history of English-language theater.

Despite this resounding popularity and proven longevity, most books written about the duo have focused on the authors rather than the works. With this detailed examination of all fourteen operas, Gayden Wren fills the void. His bold thesis finds...