Now a full-fledged Ranger responsible for a sleepy fief, Will finds a new adventure seeking the traitors who poisoned the king, investigating rumors of sorcery, and trying to rescue his friend Alyss, who is taken hostage.
When Camp Half-Blood, the only safe haven for demigods, comes close to being overrun by mythological monsters, Percy must find his best friend Grover, who is prisoner on an island in the Bermuda Triangle, and then set out to save the Camp.