内容简介：
Fourteen-year-old Sam Rivers lives on a farm in rural South Australia and when he, his dog Blackie, and three friends from a neighboring farm set out to explore the eerie sand hills at the back of his farm, they discover the perfect place to build a fort. The night before the four friends embark to begin creating their fort with a secret lookout, twenty more sheep disappear from a property down the road. Sheep rustling is rampant and when Sam and his friends discover strange tire tracks by their fort, they realize the rustlers are preparing to raid Sam's farm. The four boys scheme to catch the gang responsible by lying in wait in the fort during the night and then reporting the rustlers to the police. But even the best laid plans have faults. Sam and his friends put their lives in danger while trying to catch the rustlers, but are even more dismayed to discover they have been betrayed by a trusted friend. Locked in shearer's quarters with an old couple, Sam must find a way out, but in the end, it is up to man's best friend to try to save them all.