Part One: The Prophecy
* Chapter 1: The Prophecy - Percy is in a state of confusion, caught between the world of mortals and Camp Half-Blood. He receives a vision of a monster attacking the camp.
* Chapter 2: The Missing Camper - The chapter introduces the situation at Camp Half-Blood: Grover is missing, and Percy is the only one who can find him.
* Chapter 3: The Oracle's Warning - Percy visits the Oracle for guidance. He gets a vague and cryptic prophecy about the "Sea of Monsters."
* Chapter 4: The Old Friends - Annabeth, Grover's best friend, and Luke, a popular camper, offer their help in the quest.
* Chapter 5: The Trip to New York - The group travels to New York to visit a powerful oracle, Clarisse La Rue, and her father, Ares.
* Chapter 6: The Oracle's Secret - Clarisse reveals the Oracle's secret: the "Sea of Monsters" is actually the mythical island of "The Island of the Blessed," and they need to find the Golden Fleece.
* Chapter 7: The Quest Begins - Percy, Annabeth, and Luke set sail for the Sea of Monsters on the Argo II, a magical ship built by the demigods.
* Chapter 8: The Storm - The group encounters a fearsome storm while traveling, facing attacks by mythical creatures.
* Chapter 9: The Fury - Percy encounters Alecto, a Fury who tries to capture him. He narrowly escapes thanks to Luke's intervention.
* Chapter 10: The Island of the Blessed - The group finally reaches the island, but it's surrounded by a powerful force field.
Part Two: The Island of the Blessed
* Chapter 11: The Sea of Monsters - The group faces a terrifying encounter with the sea monsters, revealing the true danger of the sea.
* Chapter 12: The Cyclops - They encounter a Cyclops, who turns out to be a friendly creature, but also reveals that the island is being corrupted by an unknown force.
* Chapter 13: The Sacrifice - Luke, a supposed friend, reveals he has been working with the enemy and tries to sacrifice Percy to gain control over the Golden Fleece.
* Chapter 14: The Choice - Percy, determined to save his friends, makes a difficult choice: to sacrifice himself to save Luke and Annabeth.
* Chapter 15: The Golden Fleece - Percy and Annabeth locate the Golden Fleece, but its power is weakening.
* Chapter 16: The Enemy - The true enemy, Kronos, is revealed to be behind the corruption of the island. He is planning to use the Golden Fleece to gain power.
* Chapter 17: The Escape - The group escapes the island with the Fleece, narrowly avoiding Kronos's forces.
* Chapter 18: The Chase - They are chased by a monstrous creature, the Fury, across the sea.
* Chapter 19: The Rescue - Percy and Annabeth are rescued by a group of demigods from Camp Half-Blood, but Luke is captured by Kronos's forces.
Part Three: The Battle
* Chapter 20: The Enemy’s Plan - The group returns to Camp Half-Blood, where they discover that Luke has been working for Kronos, and that the camp is in danger.
* Chapter 21: The Battle of Camp Half-Blood - Kronos's forces attack the camp, leading to a fierce battle between the demigods and the monsters.
* Chapter 22: The Enemy's Weapon - Kronos reveals his weapon: a powerful monster, Typhon, who is released to destroy the camp.
* Chapter 23: The Golden Fleece - The group uses the Golden Fleece to restore Camp Half-Blood, but Typhon is still a formidable threat.
* Chapter 24: The Hero's Journey - Percy faces Typhon in a desperate battle, using his powers to defeat the monster.
* Chapter 25: The Final Choice - Percy makes a crucial choice, using the Golden Fleece to save Camp Half-Blood, even though it means he can't save Luke.
* Chapter 26: The End of the Prophecy - The prophecy is fulfilled, and the camp is saved. Percy and Annabeth are hailed as heroes.
Epilogue: The epilogue reveals the fate of Luke, who chooses to fight against Kronos, even though he is trapped in the enemy's camp.