Emily is contending with great changes, including diminished powers, but goes to London to rescue Agent B and others from the CRU, where she makes horrible discoveries about the agency's history.

For an extra credit project, Aphrodite begins a club for matchmaking mortals, which brings her to Egypt and face-to-face with her competition, the Egyptian goddess Isis.

Percy, expelled from six schools for being unable to control his temper, learns the truth from his mother that his father is the Greek god Poseidon, and is sent to Camp Half Blood where he is befriended by a satyr and the demigod daughter of Athena who join him in a journey to the Underworld to retrieve Zeus's lightning bolt and prevent a catastrophic war.

"Odin, the ruler of the Asgardians, has an important mission for Demon. Goldbristle, the gods' prized shining boar, is losing his light. Now Demon must travel to Asgard in the North to search this cold, snowy land for anything that might cure this beast"--Page [4] of cover.

The fourteen Olympians follow rumors of the Titans' escape to Olympus, but just as they reach the sea the group encounters Gaia, who offers her help in defeating Cronus. Gaia is on the side of the Olympians, partly because she believes that they will be better for the planet than Cronus, but also because she is angry with her son. He has imprisoned his three brothers: Briar, Kottos, and Gyes. She says if the Olympians free them from Tartarus, they...

Zeus the hamster will not allow the new hen at the Pet Center to join the ranks of the Olympians until she completes the labors of Hairy-clees.

"The Underworld usually isn't really meant to be a fun place - but tell that to Hades! He loves the dark and the stinky smell of sulfur. However, there is one thing that Hades is not a fan of: dogs. And when Zeus and his fellow Olympians encounter Cerberus - a snarling, three-headed dog - Hades must conquer his fears and tame the hound so everyone can continue into the Underworld and deposit their Titan prisoner, Oceanus, back where he belongs!"--Information...

When ten-year-old Zeus is kidnapped, he discovers he can defend himself with a magical thunderbolt.

"Demon returns to Olympus to find a mysterious note on his bed. Come quickly! Unicorn emergency! it says. The goddess Artemis's precious herd of wild unicorns are very sick, and if Demon doesn't save every single one, she has promised to make hound food of him!"--Page [4] of cover.

Priding herself on having the most up-to-date information about everyone at Mount Olympus Academy, gossipy Pheme sends VIP messages that linger in cloud letters above her head, a habit that raises the ire of her fellow goddesses.