The son of Neptune / Rick Riordan.

Enhanced descriptions from Syndetics:

Percy is confused. When he awoke after his long sleep, he didn't know much more than his name. His brain-fuzz is lingering, even after the wolf Lupa told him he is a demigod and trained him to fight. Somehow Percy managed to make it to the camp for half-bloods, despite the fact that he had to continually kill monsters that, annoyingly, would not stay dead. But the camp doesn't ring any bells with him.

Hazel is supposed to be dead. When she lived before, she didn't do a very good job of it. When the Voice took over her mother and commanded Hazel to use her "gift" for an evil purpose, Hazel couldn't say no. Now, because of her mistake, the future of the world is at risk.

Frank is a klutz. His grandmother claims he is descended from ancient heroes and can be anything he wants to be, but he doesn't see it. He doesn't even know who his father is. He keeps hoping Apollo will claim him, because the only thing he is good at is archery--although not good enough to help the Fifth Cohort win at war games. His big and bulky physique makes him feel like a clumsy ox, especially in front of Hazel, his closest friend at camp. He trusts her completely--enough, even, to share the secret he holds close to his heart.

Beginning at the "other" camp for half-bloods and extending as far north as the land beyond the gods, this breathtaking second installment in the Heroes of Olympus series introduces new demigods, revives fearsome monsters, and features other remarkable creatures, all of whom are destined to play a part in the most important quest of all: the Prophecy of Seven.

Reviews provided by Syndetics

School Library Journal Review

Gr 5-9-No one does cliff-hangers quite like Riordan. In this installment in this series, he jumps off the one he left at the end of The Lost Hero (Hyperion, 2010) and hits the ground running. Percy Jackson makes a long-awaited reappearance on page one, with almost no memory of his identity, except for hazy recollections of a girl named Annabeth. He's in San Francisco, home of Camp Jupiter. It's the other camp for demigods, only here, the gods appear in their Roman forms. Most of the campers are suspicious and scared of Percy, but misfits Hazel and Frank welcome him. The demigod world is in an uproar. Monsters keep reappearing after they're killed, and the campers discover that it's because Thanatos, better known as Death, has been chained by Gaea, goddess of the earth. They must go on a quest to free him, and the heart-pounding adventure amps up even more. Riordan's ability to create characters that readers care about is extraordinary. Hazel, daughter of Pluto who leaves precious gems jumping from the ground in her path, and Frank, son of Mars who just might be the key to everything, are two of the most endearing demigods introduced so far. The vernacular of today's teens is captured masterfully, making the writing fresh and funny. The ending will make readers smile, even though they'll need to wait for the rest of the story. It can't come soon enough.-Mandy Lawrence, Fowler Middle School, Frisco, TX (c) Copyright 2011. Library Journals LLC, a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.

Booklist Review

Percy Jackson is back! Following his absence in The Lost Hero (2010), book 1 of the Heroes of Olympus series, Percy returns to fight another day, and another, and another, and yes, several others. As the story begins, he clashes with two Gorgons and finds Camp Jupiter, the modern West Coast refuge for demigods. There, he befriends Frank and Hazel, who join his quest to free Thanatos (aka Death) from Gaea's evil minions in Alaska. Personal challenges, fierce battles, and self-discovery await the three teen demigods, even as Percy struggles with amnesia. Though diverse in ethnicity, physical characteristics, and magical gifts, Percy's friends in both series seem relatively interchangeable. Still, Riordan creates an original minor character in Ella, the lovable harpy. While the narrative includes lengthy explanations, flashbacks, and dreams, there is plenty of fast-paced action, including combat scenes with formidable enemies, as well as occasional comic relief. Along the way, readers will learn more about both the ancient Roman gods and the Roman legions. Fans will find plenty to cheer about as Percy and his allies move slowly toward fulfilling the mysterious Prophecy of Seven.--Phelan, Carolyn Copyright 2010 Booklist

Horn Book Review

This second book in the series (The Lost Hero, rev. 1/11) has Percy Jackson arriving at Camp Jupiter, the camp for half-blood children of the Roman gods, unable to remember his past and pursued by two gorgons who won't stay dead when he kills them. Almost immediately Juno sets Percy a quest: with the help of Hazel, a daughter of Pluto brought back to life after dying in 1942, and Frank, a son of Mars whose life is tied to a half-burned stick of firewood, Percy must free the death god Thanatos from the giant Alcyoneus's imprisonment, or it won't just be gorgons who won't stay dead. The problem? There's the possibility that once freed, Thanatos will enforce Hazel and Frank's deaths as well. In this action-packed sequel, Percy Jackson plays a lower-key but still vital role, allowing Frank to develop as a leader and leaving space for a sweet Frank/Hazel attraction to grow. Gods and monsters throw up obstacles for the adventurers, but it is the young people's own struggles against shameful things in their pasts that make these Roman demigods so sympathetic. As always, Riordan gives his heroes the last word, supplying them with sardonic quips in the face of unassailable odds -- the sort of grin-in-the-face-of-death bravado that makes his devoted fans stand up and cheer. anita l. burkam From HORN BOOK, Copyright The Horn Book, used with permission.

Kirkus Book Review

Copyright Kirkus Reviews, used with permission.