The Sphinx's Secret (The Supernormal Sleuthing Service Bk. 2)

Living in a hotel full of monsters isn’t always easy. Stephen is trying to adapt as quickly as he can, but there’s still a lot he doesn’t know. When a sorcerer casts a spell on the hotel and all its inhabitants, Stephen and his friends must find a way to undo the magic before their home is changed forever. This mystery-adventure with a time-travel twist is Hotel Transylvania meets Escape from Mr. Lemoncello’s Library.