Dave Madigan is running nearly 500 head of horses on open range. But it will take some doing to round up 50 horses single-handedly and drive them 100 miles to Fort Patterson. If he misses his deadline, he'll lose the army contract and his ranch besides. With only four days, it looks like he may make it, until someone starts shooting up his cabin and rustling his herds.
Sheriff Matt Fisher is puzzled, but he has a notion of who is responsible. Suddenly, Madigan is wearing a deputy's badge and realising that he must fight against a hidden enemy with his whole future hanging on a shot in the dark.