Gower appears to set the stage for Act III.
One day a messenger arrives to Pentapolis with a letter. Simonides shows the letter to Pericles who in turn shows it to Thaisa. It’s a letter urging Pericles to hasten his return to Tyre. Antiochus and his daughter are dead, and the lords of Tyre will make Helicanus their king unless Pericles returns within twelve months. So Pericles and Thaisa, who are now man and wife with a child on its way, set out to sea. They are halfway to Tyre when a terrible storm tosses the ship helter skelter. Midst the storm, Thaisa gives birth to a baby which is healthy and sound, but the mother fails to survive the combined distress caused by the storm and the process of giving birth.
Knowing that Thaisa is being adversely affected by the storm, Pericles petitions the gods to slacken the storm but to no avail. Alas, Lychorida, the nurse and midwife, informs Pericles that Thaisa has died while giving birth to their baby. Still, the baby is alive and well, Lychorida says, adding that Pericles should take comfort in that and be strong for the baby‘s sake. Taking his child in his arms, Pericles wishes her a life that is in stark contrast to the unruly, tempestuous one that the storm is carving out for her in this her first phase of her life. Anon, a sailor informs Pericles that Thaisa’s dead body must be given immediate burial at sea lest the storm dog the ship indefinitely. It sounds like superstition to Pericles but he is persuaded to do as the sailors ask as they speak from experience.
The storm has brought them near Tharsus, and Pericles decides to go there for the sake of the baby to whom the voyage has proven to be too stressful.
We are Ephesus in the company of Lord Cerimon who is renowned in the arts of medicine. He is explaining to some gentlemen, who have come to him to find solace what with the violence of the storm that has kept them up all night, that he--Cerimon--holds a higher regard for his skill and knowledge in medicine than he would for all the riches of the world when a servant appears hauling a casket that has just recently washed up on shore. Cerimon urges them to open it. They open it, revealing for the world to see a dead woman, fragrances, jewels and gems, and a scroll. Cerimon reads the scroll which indicates that the dead woman is the daughter of a king and the wife to a prince named Pericles. Pericles begs the reader to have the kindness to give the body proper burial for which jewels and gems have been provided as recompense. Studying the corpse, Cerimon determines that the body had only just recently expired, meaning that his medicine may yet bring it back to life. Sure enough, application of his art does the trick and Thaisa revives. She is carried away to be properly cared for.
Pericles has arrived at Tharsus. There he entrusts Cleon and Dionyzia with the care of his daughter, who is named Marina for having been born at sea. Pericles himself must quickly repair to Tyre which is embroiled in a political crisis. Dionyzia expresses her sorrow for having been denied the pleasure of meeting Thaisa. Pericles argues that no matter what man does the gods will have their ways. To console and comfort Pericles, Cleon assures Pericles that he and Dionyzia will look after Marina as if she were one of their own. Pericles doesn’t doubt it. He bids Lychorida, who will stay with Marina, goodbye.