Hardy Boys 19: the Disappearing Floor

Once again Frank and Joe Hardy take on a puzzling case when their famous detective father asks the boys to assist him in tracking down a notorious jewel thief and his accomplices. The trail leads to the outskirts of the Hardys’ home town and to a weirdly guarded mansion on the old Perth estate. With their pal Chet Morton the brothers must tackle 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.