Nahnya Crossfox leaves her Indian settlement in the Sealed Valley, an area encrusted with virgin gold, to find a doctor for her ailing mother. Upon seeing the gold Nahnya offers him in pre-payment, Doctor Cowdray of Fort Edward agrees to make the dangerous seven-day journey to the settlement. During the trip, Cowdray falls in love with Nahnya, but she refuses his proposal, fearing the consequences of a mixed blood marriage. After stumbling on a secret, gold-laden cavern, Cowdray returns to Fort Edward but, lovesick, decides to make the trip back to the valley. Cowdray is thrown into river rapids by two gold-hungry thieves but is rescued from drowning by Kitty Sholto, a miner’s daughter. The thieves try to penetrate the valley but are repelled by a group of Indians led by Nahnya. Sacrificing her love for Cowdray, Nahnya encourages the doctor to marry Kitty and returns to her tribe alone.