Once again Frank and Joe Hardy accept the challenge of 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 Hardy s home town and to a weirdly guarded mansion on the old Perth estate. Author: Franklin W. Dixon Reading Level: Ages 8 to 14 years Publisher: Penguin Group USA Format: Hardcover, 192 pages ISBN: 9780448089195