Gilbert and Lana Martin (Henry Fonda and Claudette Colbert) are a young couple trying to make a home in New York State's Mohawk Valley, but repeated attacks by Indians drive them, along with other settlers in the valley, into a nearby fort, where they watch helplessly as the natives lay waste to their farms and cabins. Gilbert joins the militia, who must do battle both with the local Indian tribes and the British soldiers who are provoking them to battle. Gilbert returns wounded, and as he recuperates, a healthy crop rises in the fields, but their satisfaction is short lived when the Indians once again hit the warpath.