Eli Riley is the marshal of Murphy's Ford, a copper mining town. But when the town's water supply is poisoned, the copper company is blamed. Then trouble starts: two prominent citizens are killed and a stranger arrives looking to avenge their deaths. Murphy's Ford is divided, and a vigilante mob heads for the mine owners. Eli, involved in a shoot-out, as the water poisoners become known, faces a growing demand for their lynching. How would it all end?