In 'Tosca', Puccini explored the dark side of human emotion, a marked change from the late-Romantic sentimentality of 'La Boheme'. Also in contrast to 'La Bohème' where the villain was fate and so the stage action was minimal, both heros and villains are humans who struggle on stage, and the clashes are always between single individuals. It is a story of cheating and doubt - nothing seems honest and direct, even love is troubled by jealousy.
Luigi Illica and Giuseppe Giacosa based the libretto on Victorien Sardou's play La Tosca (1887). This is the Schirmer edition of the Vocal Score and contains an English version by John Gutman.