Gower enters, narrating the passage of time. Now Pericles is settled as a king on Tyre, Thaisa is a priestess in Ephesus, and Marina has become a young woman in Tarsus. Cleon has another daughter who spends all her time with Marina, but Cleon's daughter, now of marriageable age, does not hold up next to the nearly perfect young Marina. Marina receives all the praise, and Dionyza is wildly envious; she makes plans to murder Marina so that her daughter alone may receive praise. When Marina's nurse Lychordia dies, Dionyza is ready. She hires Leonine, a murderer.
With Gower's monologue finished, Dionyza makes Leonine swear to never tell who ordered the death of Marina. Marina enters to strew flowers on Lychordia's grave, moaning: "Ay me, poor maid, / Born in a tempest when my mother died, / This world to me is but a ceaseless storm / Whirring me from my friends" (IV.i.69-72). Dionyza notes how pale she is, and suggests she takes a walk along the sea with Leonine. Marina agrees grudgingly.
As they walk, Marina speaks of the tempest in which she was born, and what her nurse had told her of her father. Leonine tells her to say her prayers, and that he will kill her. Marina asks why Dionyza would have her killed, when she has never done a bad thing to anyone. Leonine says he doesn't know the reason, just his duty. Marina asks him to come between Dionyza and herself, and spare her, rather than killing her. Then several pirates enter, scaring Leonine. The pirates take Marina, and Leonine decides to tell Dionyza that he killed Marina and threw her in the sea.
In Myteline on the island of Lesbos, Pander, who runs the brothel, and Bawd, who supplies the prostitutes, enter with their man Boult. They discuss their need to get to women for the brothel, having already raised a number of girls to the profession. Boult goes to look in the market, and Pander and Bawd discuss retiring, since prostitution is a bad vocation.
Then Boult enters with the pirates and Marina. Pander decides to buy her, and Bawd and Marina talk. Marina wishes that Leonine had succeeded in killing her. Bawd says that she will be content to live in pleasure, with gifts from all the gentlemen. Since she is a virgin, Bawd has Boult advertise Marina in the marketplace, assuming many men will line up for the opportunity to take her virginity.
Bawd tells Marina she must not weep, as none will have a good opinion of her then. Bawd promises Boult that he will be allowed to sleep with Marina too, and sends him off to advertise her more thoroughly. Marina swears to Diana that she will stay a virgin.
Like Thaliart's failed effort to kill Pericles, Leonine also fails in his task and lies about it, to save face. While we don't know what happened with Thaliart--whether he returned to Antioch with news of Pericles's death--in this case we will find out what happens to the murderer.
While the attempt on Marina's life duplicates the assassin's attempts to kill Pericles, Marina's apparent death also doubles the alleged death of her mother Thaisa. Yet again the sea bears her away, in the form of seagoing pirates. Pericles's misfortunes multiply, though he doesn't yet know it.
Dionyza's jealousy toward Marina was apparently stronger than her desire to pay back Pericles for his good deeds. In a play that rather simply breaks down between characters that are good and bad, Cleon and Dionyza clearly fall on the side of bad: they not only attempt to murder an innocent, but to murder the innocent daughter of a man who had saved his country from starvation. In Gower's comments about Antiochus and his daughter the play also has set up a rather predictable structure of punishment for the bad and reward for the good. In becoming doubles of Antiochus and his daughter, Cleon and Dionyza now fit, perhaps too snugly for comfort, into this paradigm.
Like the fisherman, the common people in the brothel at Myteline also speak in prose rather than verse. Their language is bawdy and filled with sexual innuendoes. These occasional scenes with common people probably provided some comic relief for the audience, and also gave the common people a chance to see themselves represented on stage. The scenes with the common people are often the most purposefully comedic.
Marina, being the offspring of good people but now sold into prostitution, faces a fate similar to her father's. Her resolute promise to protect her virginity mirrors Pericles own rigid, simple goodness, but at this point, there remains a question about whether she will be able to maintain that purity in the face of the new world she has had thrust upon her.