Demigod Percy Jackson, still with no memory, and his new friends from Camp Jupiter, Hazel and Frank, go on a quest to free Death, but their bigger task is to unite the Greek and Roman camps so that the Prophecy of Seven can be fulfilled.

What dangers do runaway demigods Luke and Thalia face on their way to Camp Half-Blood? Are Percy and Annabeth up to the task of rescuing stolen goods froma fire-breathing giant who doesn't take kindly to intruders? Rick Riordan answers these questions and more in three never-before-seen short stories that provide vital back-story to the Heroes of Olympus and Percy Jackson books. A special bonus story marks the publishing debut of Rick Riordan's son...

"The Greek and Roman demigods will have to cooperate in order to defeat the giants released by the Earth Mother, Gaea. Then they will have to sail together to the ancient land--Greece itself--to find the Doors of Death." -- Publisher.

"The Greek and Roman demigods will have to cooperate in order to defeat the giants released by the Earth Mother, Gaea. Then they will have to sail together to the ancient land--Greece itself--to find the Doors of Death." -- Publisher.

At the conclusion of The Mark of Athena, Annabeth and Percy tumble into a pit leading straight to the Underworld. The other five demigods have to put aside their grief and follow Percy's instructions to find the mortal side of the Doors of Death. If they can fight their way through the Gaea's forces, and Percy and Annabeth can survive the House of Hades, then the Seven will be able to seal the Doors from both sides and prevent the giants from raising

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The Greek and Roman demigods must simultaneously prevent the earth mother, Gaea, from waking and stop war from breaking out at Camp Half-Blood.

Jason, Piper, and Leo, three students from a school for "bad kids," find themselves at Camp Half-Blood, where they learn that they are demigods and begin a quest to free Hera, who has been imprisoned by Mother Earth herself.

"THE LIGHTNING THIEF: Zeus's master lightning bolt has been stolen and Percy Jackson is the prime suspect. He and his friends have ten days to find and return it and bring peace to a warring Mount Olympus. To succeed, Percy has come to terms with the father who abandoned him, solve the riddle of the Oracle that warns of betrayal by a friend, and unravel a treachery more powerful than the gods themselves. THE LOST HERO: Jason, Piper, and Leo find themselves...