With only the slender clue of an arrow-shaped tie clasp, Frank and Joe Hardy pick up the trail of the cunning gang of thieves responsible for a wave of jewelry-store holdups. But their investigations are interrupted when a desperate plea for help comes from their widowed cousin who lives on a cattle ranch in New Mexico. Frank, Joe, and their pal Chet Morton fly there immediately. The mysterious disappearance of one cowboy after another has given Crowhead Ranch the reputation of being jinxed, and it is quickly being stampeded toward financial ruin. The young detectives face grave danger before they uncover a cleverly conceived plot engineered by the crooked arrow gang. In a dramatic climax Frank, Joe, and Chet aid law-enforcement officers in smashing the highly organized band of criminals, putting an end both to the troubles at Crowhead ranch and the jewelry-store robberies. - Flyleaf.