A scam artist convinces a naive young woman in Whitman, Montana, that she is to be given a job by a major Chicago discount store. However, her dad and mom see through the ruse and tries to have him run out of town.
At this point, the man confesses that he has a letter from a man who recently died in prison. The letter indicates that the young woman was fathered by him and a woman named Estelle and was placed in this couple's care, which they are forced to admit.
This leads the young woman into a search for her real mother, who it turns out is a Blackfoot woman living in the "Hi-Line", a desolate area in Montana.