Hardy Boys 19: the Disappearing Floor

Frank and Joe Hardy once again tackle a puzzling case when their famous detective father asks them to assist in tracking down a notorious jewel thief and his accomplices. The trail leads to the outskirts of the Hardys’ hometown and to a weirdly guarded mansion on the old Perth estate. With their pal Chet Morton, the brothers must solve the mystery of the mansion heir’s sudden death. A disappearing floor, a huge, savage-looking hound, a galloping ghost, and a college professor’s startling invention are just a few of the strange elements that complicate the boys’ efforts to solve both mysteries.