This is the fourth book in the Percy Jackson series. In the beginning, Percy is at his new school's orientation during which he defeats two empousa who attack him. At Camp Half-Blood, Percy, Annabeth, Grover, and Tyson are chosen to go on a quest in the labyrinth to look for Daedaus, the creator of it. In the labyrinth, they meet the goddess Hera, but she leaves after Annabeth infuriates her. Later, Percy finds himself inside Mt. St Helens at a forge used by Kronos. Inside the volcano, Percy causes an explosion that makes the volcano erupt and awakens the most evil monster, Typhon. Percy is shot out of the volcano and lands on an island and meets Calypso. Percy chooses to leave Calypso to help his friends when Hephaestus comes to get him. After entering the Labyrinth again with the others, he comes across the Triple G ranch where he meets Nico di Angelo. He then battles the owner of the ranch who has three hearts. They travel farther, and they find Daedalus. He meets Rachel, and they get back to camp. When they get back to camp, Rachel becomes the new oracle.
This was one of my favorite books in the series of Percy Jackson. My favorite part was when Percy is at the Triple G ranch and has to clean the flesh-eating horse pen. I would recommend this to people if they have read the other books before this, and they are interested in ancient Greek history and action adventure books. I would rate this a four out of five stars, because sometimes things happen instantly and the end confused me a little bit.