Empousai disguised as cheerleaders attack Percy at Goode High School orientation.

Percy and Annabeth travel to Camp Half-Blood to warn campers about Luke's invasion plan.

Percy and Annabeth accidentally fall into the hidden Labyrinth entrance beneath Zeus's Fist.

Annabeth is chosen to lead the official quest into the Labyrinth to find Daedalus.

Percy, Annabeth, Tyson, and Grover descend into the Labyrinth to begin their quest.

Hera appears inside the maze and grants Annabeth one wish.

Percy and his friends find and free the Hundred-Handed One Briares from Alcatraz Prison.

Percy makes a deal with the monster Geryon to clean horse stables in exchange for Nico's freedom.

Percy kills Geryon by shooting a single arrow through all three of his hearts at once.

Percy causes Mount St. Helens to erupt and is blown onto the island of Ogygia.

Percy and Annabeth recruit mortal Rachel Elizabeth Dare to guide them through the Labyrinth.

The group reaches Daedalus's workshop and discovers Quintus is Daedalus, who gave Luke Ariadne's String.

Kronos rises fully formed by using Luke Castellan's body as his vessel.

Waves of monsters erupt from the Labyrinth and clash with defenders at Camp Half-Blood.

Daedalus chooses to die, destroying the Labyrinth and cutting off the Titan army's route into camp.

The story begins when disguised monsters attack Percy at a high school orientation, warning him that Luke's Titan army plans to invade Camp Half-Blood. Annabeth leads an official quest into the ancient Labyrinth to find the legendary inventor Daedalus before Luke can use him to navigate the maze. The questers battle monsters and encounter gods throughout the Labyrinth, eventually learning that the camp's mysterious sword master has been Daedalus all along — and that he has already given Luke the means to invade. Kronos fully awakens by possessing Luke's body, and the Titan army erupts from the Labyrinth to attack Camp Half-Blood. The battle is turned by unexpected heroes who change sides at the last moment, and Daedalus ultimately sacrifices himself to destroy the Labyrinth and seal the threat.

The headline events of Percy's quest to stop the Titan invasion.

Rachel helps Percy escape the monster attack and fire at Goode High School.

Grover stands trial before the Council of Cloven Elders and is given one week to find Pan.

Annabeth secretly shares her Labyrinth scouting mission with Percy, Tyson, and Grover at the Poseidon table.

Quintus gives Percy a single-use whistle that will summon Mrs. O'Leary in an emergency.

Janus confronts Annabeth in a mosaic room and forces her to choose between two tunnels.

Kampe breaks through a prison wall in pursuit of the group, driving them back into the Labyrinth.

Nico summons the ghost of Bianca, who tells him to stop blaming Percy and abandon his resurrection mission.

A freshwater naiad refuses to let Percy pollute her river to clean Geryon's stables.

Annabeth refuses to answer the Sphinx's trivia test, forcing the group to fight their way past it.

Percy wakes on Calypso's island, Ogygia, where she heals his burns.

Percy returns to Camp Half-Blood to find the campers holding a funeral ceremony for him.

Minos and Kelli arrive at Daedalus's workshop and drag Nico in in chains as their prisoner.

The group finds Tyson cradling an unconscious Grover beside an underground river near Pan's cave.

Briares emerges from the Labyrinth during the battle and buries Kampe under hundreds of hurled rocks.

Poseidon visits Percy's 15th birthday party in human form and gives him a sand dollar for future use.

Before the quest even begins, Percy's world is complicated by a mortal girl who can see through the Mist, a satyr whose life's purpose hangs by a thread, and a mysterious new sword master at camp who raises suspicions. Inside the Labyrinth, the questers are detained, imprisoned, tested, and separated as they navigate a maze that constantly defies logic and strategy. A side mission splits the group, sending Tyson and Grover toward Pan while Percy faces catastrophe at Mount St. Helens and wakes on a paradise island that offers him an impossible escape. After Percy returns, unexpected allies — a reluctant automaton, a grieving inventor, and a legendary Hundred-Handed One — emerge from the Labyrinth to turn the tide of the final battle. The story ends with a visit from a god bearing warnings and gifts that hint at struggles still ahead.

The supporting encounters and moments that shaped the quest.

Percy tells Rachel the truth about Greek gods and monsters, confirming she can see through the Mist.

Percy intercepts an Iris message of Nico asking King Minos for details about a soul-exchange resurrection.

Annabeth omits the final line of the quest prophecy when reciting it to the assembled camp.

Percy deduces that Quintus must be a spy for Luke after Chiron suggests Kronos needs an automaton body.

The ghost of Theseus warns Nico that mortal love — not Ariadne's String alone — was what guided him through the maze.

Briares loses hope in himself and abandons the group after escaping Alcatraz Prison.

Hephaestus reveals it was Hera — not Zeus — who threw him off Mount Olympus as a baby.

Tyson and Grover split from the quest to follow a tunnel Grover senses leads toward Pan.

Annabeth kisses Percy before using her invisibility cap to escape the telekhines at Mount St. Helens.

Hephaestus visits Ogygia and tells Percy that a clear-sighted mortal is the key to finding Daedalus.

Percy chooses to leave Calypso's island rather than stay and escape his prophecy and the war.

Percy dreams of Luke discussing Ariadne's String and Quintus's ongoing spy mission inside Camp Half-Blood.

Ethan Nakamura pledges loyalty to Kronos and presents him with the newly forged scythe.

Pan appears to the group in a hidden cave and asks Grover to release him from existence.

Annabeth finally reveals the long-hidden final line of the quest prophecy to Percy at summer's end.

The story turns on a series of revelations that reframe both the quest and the characters making it — from Percy confirming that a mortal girl can truly see monsters, to Annabeth secretly hiding a prophecy line that could mean Percy's death. Inside the Labyrinth, gods expose their own hypocrisies, a legendary hero proves smaller than his myth, and a ghost urges a grieving boy to let go of his anger. Percy's near-death at Mount St. Helens leads to a private crisis of purpose on an island paradise, where he must decide whether to abandon his fate or return to his friends. The final act brings a cascade of revelations — a traitor's true allegiance, a lost god's farewell, and a young demigod's discovery that may be the only way to stop Kronos — each one shifting the shape of the war to come.