The story concerns a love triangle. The protagonist, Dick Forrest, is a rancher with a poetic streak (his "acorn song" recalls London's play, "The Acorn Planters"). His wife, Paula, is a vivacious, athletic, and sexually self-aware woman, who falls in love with Evan Graham, an old friend of her husband. Unable to choose between the two men, she wounds herself mortally with a rifle in what her husband is certain is a suicide.

Biographer Clarice Stasz writes that the book is "not autobiography", but speaks of London's "frank borrowing from his life with Charmian", his second wife, and says it is "psychologically valid as a mirror of events during [the] winter [of 1912–13]". Paula, like Charmian, is subject to insomnia and is unable to bear children. Based on a reading of Charmian's diary, Stasz identifies Evan Graham with two real-life men named Laurie Smith and Allan Dunn.

Even minor characters can be identified; Forrest's servant Oh My resembles London's valet Nakata. The long-bearded hobo philosopher Aaron Hancock resembles Frank Strawn-Hamilton, who was a long-term guest at the London ranch. Sculptor Haakan Frolich makes an appearance as "the sculptor Froelig", and painter Xavier Martinez appears under his own name.