Tosca is an opera caught between truth and lies. Set in real places, at real times, it is probably the opera Puccini researched most scrupulously in order to ensure historical accuracy. Yet insincerity is its main theme: the opera's principal events are structured around a series of deceptions that intensify in dramatic power and consequence over the course of the work. Act I: Cavaradossi lies to Tosca in order to conceal the fact that he is sheltering Angelotti, the political prisoner. Act II: Tosca makes a false bargain with Scarpia, agreeing to succumb to his lustful advances and then stabbing him as he is about to claim his prize. Act III: Scarpia's deceit is revealed when the ‘fake’ execution he has arranged for Cavaradossi turns out to be for real. Furthermore, Tosca is a performance about performance, with its fictional characters constantly donning masks: Tosca is a singer and actress by profession; Cavaradossi prepares to feign his own death; Scarpia conceals his malevolent nature behind a clerical façade. With its strains of verismo and Grand Guignol, Tosca is arguably Puccini's most self-consciously ‘theatrical’ opera, its high drama epitomised most vividly at the moment when Tosca places a crucifix on Scarpia's chest and floodlights his corpse by surrounding it with candles. Beyond the basic level of plot, contemporary spectators perceived yet further layers of insincerity in Tosca that, as we shall see, permeated through the libretto and into the music itself.