On the day of his priestly ordination, the young Romualdo sees a beautiful woman in the church, who he later discovers is the courtesan Clarimonde. Sent to his parish, Romualdo is tormented by the irresistible desire to see the woman again, until one night he is called to assist her spiritually on her deathbed. Upon her arrival Clarimonde is already dead: the priest, left alone with her, cannot help kissing her cold lips. The gesture of love resurrects Clarimonde and from that moment Romualdo's personality doubles: he thus begins a life as a lover of the courtesan, during which he dreams of being a young parish priest, and another as a priest who at night dreams of meet Clarimonde in Venice. The only one to notice this double existence is Abbot Serapione, who warns Romualdo of the serious threat posed by the beautiful Clarimonde. However, the young man cannot stop loving the woman, not even when he discovers that she feeds on his blood while he is asleep. Only when Serapione shows him Clarimonde's ruined body in the tomb will Romualdo realize that he is on the verge of perdition.
