As a background to the opera Richard Langham Smith discusses the play, by the Belgian playwright Maeterlinck, and considers its literary roots. David Grayson then traces the genesis and composition of the opera, examining also the sketches and rejected versions in order to illuminate Debussy's compositional strategies. A detailed synopsis by Roger Nichols, which considers carefully Debussy's musical response to the text, forms a central chapter. Following this, the book moves on to consider more detailed aspects of the style and language of the opera. The relationship between symbols and musical motives forms the basis of a chapter by Richard Langham Smith and his subsequent chapter considers the crucial themes of darkness and light and the key-schemes used to portray them.

Two chapters by Roger Nichols on the various performances since 1902 and on the ideas of interpreters and commentators complete the text. The book concludes with a detailed bibliography and a discography.