At first cold, virginal Salome seems disgusted by life in the palace and by the lecherous Herod who ogles her. When she hears Iokanaan's voice, she is drawn to the imprisoned prophet, to the point of sexual obsession, and uses all her wiles to seduce him. Manipulative and used to getting her way, Salome tempts Herod—nearly as obsessed with her as she is with Iokanaan—to behead the prophet so she can kiss him. Her victory lasts only moments longer than the kiss, for her cruelty and abominable act cause fear and repulsion.
After deposing, imprisoning, and executing his older brother, Herod has assumed the throne of Judea. He married his brother's wife, while his brother was still alive, and now lusts obsessively after her daughter, Salome, commanding her to dance for him. As a result of his lust he is forced to have Iokanaan beheaded to please Salome. Although he has committed, or been responsible for, many sins and violent acts himself, he is shocked at Salome's debauchery, which goes even beyond his, and he fears the consequences of putting a holy man to death.
Iokanaan is the name given to the biblical figure of John the Baptist. He claims to have been raised from the dead by the son of God. He also claims the Messiah has come, and he prophecies doom. From the cistern in Herod's palace where Iokanaan is imprisoned, he curses the house of Herod and predicts its end. He specifically directs his denunciations toward Herodias by calling her a harlot and reporting aloud the extent of her adulterous and sinful ways—including her lusting after entire armies.
Herodias has married her first husband's brother and is jealous of Herod's incestuous attention to Salome and of the power, once her own, Salome now exerts. She hates Iokanaan, who denounces her lust, and is angry with her husband for protecting him. Later Herodias takes pleasure in the prophet's grisly death, although regretting her loss of power in achieving the result.