Mark of Athena

I started Mark of Athena last week and didn't get much information on the book so far. What I have gathered on the book is that Percy Jackson has been in a kind of foreign exchange program with the Roman camp and the Greek camp. Percy is sent to the Roman camp in exchange for Jason who is sent to the Greek camp. This is the first time that they have done this and now Annabeth is going to the Roman camp to retrieve Percy and return Jason. Percy is the demigod of Poseidon, the Greek god of water, Annabeth is a demigod of Athena, the Greek god of wisdom, and Jason was demigod of Jupiter, Roman god of the sky. Annabeth and Percy have a relationship and have missed each other for a long time. Jason had not been to his camp in years but still remembers every detail. The Greek camp came because they wanted to join forces against Geah, the mother of all gods.