Fur trappers Abel and Henry Iron struggle to make a living in a dying industry in the Rocky Mountains. Following in their late father's footsteps, they travel the mountains searching for beaver, carving out a meager existence in the western wilderness. When Abel encounters a band of Shoshone Indians, a misunderstanding leaves one indian dead and the Iron Brothers on the run. Together, Abel and Henry flee into the mountains to escape the warriors that are pursuing them. In the end, they will learn if the bond of brotherhood is enough to save them.