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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When she incurs Neptune's wrath by finding a diamond ring buried under rocks in the ocean, Emily is put under a curse that will force her to choose to be either a mermaid or a human and split up her parents forever.

After finally convincing her mother that she should take swimming lessons, twelve-year-old Emily discovers a terrible and wonderful secret about herself that opens up a whole new world.

The New York Times best-selling series continues with the half-mermaid embarking on an icy and perilous journey to the Land of the Midnight Sun.Strange storms are blowing up from the ocean, caused by the nightmares of Neptune, King of the Sea. Convinced that his dreams herald an approaching threat, Neptune enlists half-mermaids Emily Windsnap and Aaron for a top-secret mission to find and eliminate the source of the trouble. But Emily and Aaron quickly...

Before he can gain his freedom, Emperor Hadrian sends Julius Zebra on one last mission to Britannia where he and his fellow gladiators discover how much the Britons dislike the Romans.

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.

Leaving the safety of the demigod training ground, a disgraced Apollo embarks on a quest across North America to find a dangerous ancient-world Oracle while navigating the challenges of the evil Triumvirate.

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.

When the goddess Artemis disappears while hunting a rare, ancient monster, a group of her followers joins Percy and his friends in an attempt to find and rescue her before the winter solstice, when her influence is needed to sway the Olympian Council regarding the war with the Titans.

"Savannah Webster and her husband, Hez, have been separated since tragedy tore them apart and he began numbing his grief and guilt with alcohol. She returned to Tupelo Grove University to teach history. When Hez turns up asking for a second chance, she rejects the idea. But twenty-four hours later she's under suspicion for murder, and Hez is the best attorney she knows. They suspect the murder is tied to someone selling off the university's artifacts,...