in "The Sea of Monsters", Thalia's Tree that serves as a magical Border or protection to the Camp Half-Blood Hill was poisoned by someone. The whole camp is not safe, Chiron was fired (because he's supposed to make the camp safe, which is his responsibility) and Tantalus replace him which Percy and Annabeth didn't like it at all. Percy also discovers that Tyson,a Cyclops and friend in his school was his Half-brother but at first he couldn't accept that he has a monster-bro. But I do like Tyson. He's funny, creative and caring. The antidote for the tree is the Golden Fleece which can be found in the place called Sea of Monsters, and Clarisse, Daughter of Ares was assigned to do the quest. 
 Grover is stuck in the Sea of Monsters with a Cyclops, he needs Percy's help. Percy, Annabeth and Tyson sneaked out of the camp with the help of Hermes on their way to Sea of Monsters to get the Golden Fleece to heal Thalia's tree.. 
 Now I'm hooked with the series and Greek Mythology. I did enjoy reading the book and I like Percy's attitude in this book. He really did improve, unlike in the previous book. This book entertains me, especially Tyson. "Chicken Ponies, Fish Ponies." :)) I can't help smiling Not all Monsters are evil, some have good hearts.. Hello Titan's Curse! :D