The Metamorphoses consists of fifteen books. They can be divided into six sections. First, the narrator prays to the gods for inspiration, lays out his theme (metamorphosis), and states his intention to write a single continuous poem that stretches from the origins of the world to his own day. Second, the narrator describes the creation of the world. Primordial chaos is transformed into an orderly creation, and human life is formed. Almost immediately, humans start behaving badly. In response to the general immorality, Jupiter and his brother, Neptune, drown humanity. The only survivors are Deucalion and Pyrrha, pious people. Eventually, a new breed of humanity emerges.
The third section spans five books. In this section, Ovid focuses on the gods and their interactions with mortals. He begins with the theme of divine rape. In Book I, Apollo attempts to rape the nymph Daphne, who escapes at the last moment when her father transforms her into a laurel tree. Jupiter rapes Io, Callisto, and Europa. In Book II, the narrator recounts the story of Phaethon’s fatal chariot ride, which nearly destroys the world. In Book III, the narrator tells several stories connected to Cadmus’s founding of Thebes. He writes about the death of Actaeon and Semele, the birth of Bacchus, and Pentheus’s refusal to worship Bacchus. In Books IV and V, Ovid tells of Perseus’s victory over Atlas, his rescue of and marriage to Andromeda, and his battle with Phineus. This section ends with a song contest between the Muses and Pierides and a weaving contest between Minerva and Arachne. The Muses turn Pierides into magpies, and Minerva turns Arachne into a spider.
In the fourth section, Ovid moves into the realm of heroes and heroines. The narrator recounts the exploits of Jason, who stole the fleece from the serpent, and tells several stories about the power and magic of Medea. He explains Minos’s preparations to attack Athens, and his siege of the city of Alcathous, where Scylla falls in love with him. The narrator also tells the story of the Myrmidons’ miraculous appearance, and the sad tale of Cephalus and Procris. He describes the Calydonian boar hunt, and the sad death of Meleager at his mother’s hand. The section concludes with an extended account of Orpheus’s life and tragic death. Orpheus sings in Books X and XI about the tales of Pygmalion, Myrrha, Hippomenes, and Atalanta.
The fifth section moves us closer to the Trojan War. In Book XII, the narrator recounts Achilles’ battle with Cycnus, whom he chokes to death. Nestor tells of the battle between Caeneus and numerous centaurs. We also hear of Ceyx’s and Alcyone’s love, and Ajax’s verbal contest with Ulysses over the armor of Achilles. Ulysses defeats Ajax. Ajax commits suicide, and his blood produces a hyacinth flower. Aeneas seeks to establish his own land and defeats Turnus in battle. Ovid brings Roman history up through the successive kings of Alba and the preaching of Pythagoras, who speaks against consuming flesh and forecasts the rise of Rome. The narrator mentions Caesar and the rise of Augustus. In the sixth section, which comprises the epilogue, Ovid prophesies a glorious Roman future and the immortality of his work.
In Ovid's version, Perseus does *not* use the head of Medusa to kill the sea monster. After flying up and stabbing it in the shoulder, he then swoops down to a rock and stabs it repeatedly: "His left hand on a ridge, and with his sword stabbed time and time again the monster's groin" (IV.732 -- 33). Immediately after, Andromeda is released and they marry. This conflicts with the analysis, also, that he's not brave or heroic enough to face the creature using his own arms rather than just the Gorgon's head.