Keeper of the Lost Cities: Hurricane

After a tragedy during an inter-camp summit, Percy is transported to a strange new world by a crystal. When a strange boy with black hair and blue-green eyes light leaps to a Black Swan hideout, Sophie thinks he's an elf. She and her friends help him realize what he is, and he helps them get Keefe back. But the final battle with the Neverseen is coming, and it won't be easy.