The summer camp of Woodcrest Military Institute was always an exciting event to the Mercer boys and Terry Mackson. But when the cadets camped near Rustling Ridge, the boys ran into a series of startling occurrences: a horse stampede, a mysterious fire, the disappearance of a little girl, and most frightening of all, the Ghost of Rustling Ridge, who seemed determined to drive the cadets away. Don and Jim, along with Terry, were appointed to the camp's Ghost Patrol, and how they solved the mystery of the ghost makes one of the most exciting adventures in the Mercer Boys Series.