Perissa Trotter and the Game of Truths

What happened when the worlds of Rowling and Riordan combine into one? Perissa Trotter is about the find out as the role of the supernatural becomes ever greater on her. She receives various letters from the mysterious Department of Olympus and finally sets off to Hogwarts School of Half-Bloods and Mythology while the gods seem to be playing a game of deception, intrigue and betrayal.