Suspicion falls on members of a Jewish ghetto family that produces masks for the theater. But Tito discovers a mysterious veil that leads him in a different direction. Assisted by Augustus Rumbolt, an Englishman making his Grand Tour, Tito is soon on the trail of Dr. Palantinus, a masked figure who heads a secret society that charges exorbitant fees to partake of its enticing rituals.
But who is behind the mask of Palantinus? Tito's search for the answer pierces the treacherous depths of a city dedicated to masquerade and pleasure, where ancient hatreds thrive, cultures uneasily coexist, and where opera is the stuff of daily life.