Many years ago, John Blake, Will Blake's grandfather, on a hunt for curios among the Indians, is made love to by an Indian girl, who, after the Indian fashion of wooing, sings to him the song of lamentation, and when he waves her away she prophesies that one day one of her race will call to one of his, and the white man will answer. Years later, Will Blake, the grandson, goes into the western desert, on a hunt for radium, with Professor Edwards. His fiancée, Helen Edwards, the Professor's daughter, accompanies them. Before starting on the trip, Helen, in examining the many curious Indian relics in Blake's apartments, has a vision of an Indian girl sitting playing with a rattlesnake. Arriving in the west, the party start prospecting and Blake is bitten by a snake concealed in the cactus. Alema, a half-breed Indian girl, sucks part of the poison from his arm, and takes him to her tent, saying that in three days she will know if he will live or die. She refuses to allow anyone to see him until the allotted time. Apoe, a Navajo brave, tries to induce Alema to return to the Navajo camp. She refuses, having fallen in love with Blake. Apoe understanding, attempts to kill Blake, but is prevented by Alema. During his convalescence, Blake has become infatuated with Alema, and Helen mistaking his restlessness for symptoms of ill health, they decide to return home. They are ready to return to the east, when Blake hears Alema outside his window singing the song of Lamentation; he is irresistibly drawn to her, and follows her to her tent. Helen, seeing them going away into the desert, follows and demands that he choose between them. He decides to remain with Alema, whom Helen now recognizes as the girl of her vision. Apoe succeeds in filling Blake's water bag with poisoned water. Blake becomes sick and in his delirium calls for Helen. Alema, believing it will save his life, goes to the city for Helen, arriving on the day that she is to be married to a former sweetheart. Throwing aside her wedding garments, she hurries with the Indian to the aide of her lost love, only to find that in the absence of Alema, Apoe has murdered the sick man. The story ends with Helen and Alema, grief stricken, and wandering each in a different direction, as the sun goes down over the desert waste.