Harriet (Harry) Martin masquerades as a boy in a last ditch effort to obtain work at Ross Calvert's isolated cattle station, Devil's Ridge.
By the time Ross discovers her true identity Harry has fallen in love with him, so she puts a desperate proposition to him. Marry her and she will give his Devil's Ridge an heir.
On their honeymoon Ross meets up with his former fiancee Virginia and finds himself still obsessed with her. With the black clouds of war hovering over his head he faces a terrible dilemma. Taste Virginia's passion before he heads to the trenches of France, or keep his marriage vows to Harry.
The turmoil of war finds Harry imprisoned, defending spying charges, and Ross struggling to survive the carnage on the Western Front.