New York Times #1 best-selling authors Rick Riordan and Mark Oshiro collaborate again on a new adventure in which Nico di Angelo teams up with his half-sister Hazel Levesque to protect . . . monsters? Nico di Angelo is feeling antsy. It’s been almost three months since he and his boyfriend, Will Solace, returned to Camp Half-Blood from their journey to Tartarus, and there hasn’t been a demigod quest or a conflict with monsters in all that time. So, when Nico’s half-sister, Hazel Levesque, asks h