Set in the Yukon, it tells the story of Frona Welse, "a Stanford graduate and physical Valkyrie"[1] who takes to the trail after upsetting her wealthy father's community by her forthright manner and befriending the town's prostitute.

She is also torn between love for two suitors: Gregory St Vincent, a local man who turns out to be cowardly and treacherous; and Vance Corliss, a Yale-trained mining engineer.

Her name echoes that of his mother, Flora Wellman, though her inspiration has also been said to include London's friend Anna Strunsky.

[1] Modern commentators have criticized the novel for its approval of the main character's view that Anglo-Saxons are racially superior.

[3] The novel was commissioned by publisher S. S. McClure, who provided London a $125 a month stipend to write it.