The Sea of Monsters
Percy Jackson: The protagonist of the story. He is a 13-year-old demigod. In the book, he travels to the island of Polyphemus. The island is in the Sea of Monsters. He goes to save his friend, the satyr Grover. He also gets the Golden Fleece from the island. This helps in saving Camp Half-Blood from being destroyed. Annabeth and Tyson, his half-brother, go with him in this quest.