A terrace of Herod’s palace on the shores of Lake Galilee in 30 A.D. Narraboth is obsessed with Salome, who is inside feasting with her stepfather Herod and his court. The voice of the prophet Jokanaan is heard, echoing from a deep cistern where he has been imprisoned, proclaiming the Messiah’s greatness. Salome, bored with Herod’s lechery, rushes out to the terrace. She becomes curious when she hears Jokanaan curse Herodias, her mother, whom he denounces for her “incestuous” second marriage. When the guards refuse to let her speak to Jokanaan, Salome coaxes Narraboth, who orders that the prisoner be released. Salome is fascinated by Jokanaan’s white body and black hair, pouring out her uncontrollable desire to touch him, but the prophet rejects her. When Salome continues begging for the opportunity to kiss Jokanaan’s red lips, Narraboth stabs himself in horror. The prophet descends into the cistern, cursing the girl.

Looking for Salome, Herod appears, followed by his wife Herodias and his court. He slips in Narraboth’s blood and begins hallucinating. Herod’s thoughts return to Salome, who again spurns his overtures. Jokanaan’s subterranean voice is heard harassing Herodias, who demands that Herod turn the prophet over to the Jews. Herod refuses. Jokanaan prophesies again about the Messiah who will be “the Saviour of the world” and foretells other events which further terrify Herod and Herodias. Herod begs Salome to divert him by dancing and offers her anything she might wish in return. Salome makes him swear he will live up to his promise, then dances, shedding her veils and finishing at Herod’s feet. She shocks Herod by asking for the head of Jokanaan on a silver platter. Herod refuses and offers alternatives, but Salome persists until Herod relents. The executioner descends into the cistern, returning with Jokanaan’s head. Salome passionately seizes her reward, addressing the prophet’s head as if he were still alive and ecstatically kissing his lips. Herod commands that Salome be killed.