When it is discovered by a local doctor that a slave family is fostering Elizabeth Dumond, a white child orphaned at birth, he insists that she be raised amongst people of her own color. "She'd be better off in an orphanage than living with darkies!" he cries.

The angelic child captivates the shriveled, yearning heart of Lucille Laurent. She and her husband, Hugo, take the orphan in and raise her in their plantation home, Sweetbrier. Elizabeth retains the bond she formed with her black foster family, particularly with Sophie, her devoted friend and sister for the first five years of Elizabeth's life. She insists that Sophie join the house staff at Sweetbrier, and the two girls grow into young women cosseted and protected by the benevolent Hugo and Lucille.

When Hugo dies and Lucille falls apart, Sophie and Elizabeth suffer brutalities inflicted on them by Bert Laurent, Lucille and Hugo's son, who takes control of Sweetbrier. During Bert's violent rape of Elizabeth, the women defend themselves, resulting in the death of Bert. They flee Sweetbrier and embark on a journey west across the Southern Trail. The trip is fraught with peril and a constant fear they will be caught and hanged for Bert's murder. To complicate matters, Elizabeth discovers she is pregnant from the encounter with Bert. The women spend months enduring the hardships and hazards of the trail en route to San Diego where they board a boat heading for San Francisco.

Once in San Francisco, the women rent a room at the Wayside Inn and Lodging House. Elizabeth reinvents herself, changing her name to Liza Laurent. She gives over the care of Rose, her unwanted infant daughter, to Sophie, and devotes her time to becoming a successful business owner of an upscale bordello. Rose grows up loving her surrogate mother, Sophie, but longs for the love of her birth mother. Liza rejects Rose, finally banishing her to a boarding school. Rose becomes disillusioned and eventually closes the door on her hopes for motherly love.

Rose grows into an accomplished, lovely young woman. She meets Nolan MacDonald, owner of a shipping company based on Vancouver Island. They marry and take Sophie with them to the island. Liza, alone in San Francisco, realizes she has done irreparable damage by her rejection of Rose and longs to mend the rift between them. She phases out the bordello business and transforms the Wayside Inn into a popular restaurant and lounge.

A tragedy involving the death of Rose's husband, Nolan, and son, Robbie, causes Rose to break down. Sophie shepherds the catatonic Rose and her daughter, Aurora, to the Wayside Inn in San Francisco in the hopes of bringing Rose back from debilitating grief. It seems as if Rose is lost forever when the 1906 earthquake strikes and shakes her out of her all-consuming grief. The natural disaster unifies the four women in their efforts to help victims of the catastrophe.