Samuel Hamilton's childhood was spent in Ireland where he was self-educated from borrowed books. Although he experienced initial distrust from his California neighbors, in time, he won their hearts. Although they never achieve wealth, the Hamilton family never goes hungry. The family consists of four boys: sinless George, lucky Will, passionate Tom and lazy Joseph, and five girls: studious Una, solitary Lizzie, fun-loving Dessie, scholarly Olive (the narrator's mother who becomes a teacher) and beautiful Mollie. Liza, the mother has a will of iron. Adam joins the army, Cyrus moves to Washington D.C. to take a job at the Office of the Secretary of War, and Charles remains on the farm. He has an accident which results in a large dark brown scar which embarrasses him and makes him more reclusive and lonely.
Although discharged, Adam cannot stand the idea of returning home and after he re-enlists his father sends for him. He finds Cyrus living luxuriously with a new prosthetic leg. Cyrus attempts to convince Adam to enter West Point but Adam returns to his old regiment.
After his final discharge, Adam still cannot return to the Connecticut farm and happily wanders around the country as a hobo until he is arrested for vagrancy and placed on a chain gang. Charles receives a letter informing him of his father's death and that that his fortune of $100,000 will be split evenly between his sons.
Adam escapes from the chain gang and wires Charles to send him $100. The brothers discuss their inheritance which Charles believes is ill-gained. His father lied about his past as an Army hero. Adam suggests they leave Connecticut and go to California.
Cathy Ames makes her appearance in chapter eight. Although she looks like an angel with a lovely face and hair of gold, she is full of guile, unfeeling and without guilt. An only child, her parents adore her. She demonstrates an uncanny ability to lure men sexually. When she is twelve, she ensnares a group of teenage boys in a sexual peccadillo just to see them suffer punishment. A teacher commits suicide after an involvement with her.
For no reason, Cathy hates her parents, burns down their house and kills them.
In contrast to Samuel Hamilton's goodness, the Trask family patriarch, Cyrus, is sinful by committing, in effect, the novel's original sin, as Adam and Eve did in the Garden of Eden by disobeying God and eating the forbidden apple. And, as the first couple's descendents were cursed, so too are the offspring of Cyrus. Despite their windfall inheritance, the brothers are socially inept and miserable. Although Adam represents the slain Abel, it is he, instead of his brother Charles (Cain), who wanders the earth after his dismissal from the company of man by God. Cathy Ames, whose "aims" are pure evil, clearly represents Satan. Unfeeling, uncaring whatsoever, she tempts people sexually, and brings pain to everyone she encounters.