Ruth is a self-sufficient woman who makes her living as a ghostwriter for self-help books. She lives with her long-term boyfriend, Art Kamen, and acts as a stepmother to Art's two teenage daughters from a previous marriage, Dory and Fia. Meanwhile, as LuLing is showing signs of dementia, Ruth struggles to juggle her mother's illness, her job, and her relationship. As an adult, Ruth struggles to understand her mother and her strange behavior during Ruth's childhood. Although she loves her mother, she also resents her for having criticized her harshly when she was young and forcing her to obey strict rules. LuLing believed that young Ruth had the ability to communicate with the spirit world, and often expected her to produce messages from the ghost of LuLing's long-dead nursemaid, Precious Auntie, by writing on a sand tray.

LuLing's autobiography makes up the middle section of the book. This story within a story describes LuLing's early life in a small Chinese village called Immortal Heart. LuLing is raised by a mute, burned nursemaid called "Precious Auntie." It is later revealed that Precious Auntie sustained her injuries by swallowing burning ink resin. Although the oldest daughter in her family, LuLing is ignored by her mother in favor of her younger sister GaoLing. However, Precious Auntie was entirely devoted to caring for LuLing.

LuLing's story goes further back, describing Precious Auntie's childhood as the daughter of a local bonesetter. The teen-aged Precious Auntie is the only person who knows the location of a hidden cave where many ancient "dragon bones" can be found, knowledge that she retains even after being burned and coming to live with LuLing's family. After the discovery of the Peking Man, fossilized bones and information about where they might be found becomes extremely valuable. A local family, the Changs, wish to arrange a marriage between LuLing and their son Fu Nan because they believe that LuLing can lead them to the fossil cave. LuLing's family approves of the marriage, but Precious Auntie violently opposes it. Unable to speak in detail, she writes LuLing a long letter explaining her reasons, but LuLing does not read it to its end.

Only after Precious Auntie's death does LuLing learn that her nursemaid was actually her mother, and that the woman she had thought to be her mother is actually her father's sister. After Precious Auntie's death, GaoLing marries Fu Nan and LuLing is sent away to a Christian orphanage where she completes her education, grows up and becomes a teacher. Here, she meets her first husband, Pan Kai Jing. LuLing lives in the orphanage as a teacher through World War II, often going to extreme lengths to protect the students from the Japanese soldiers and other dangers. A few years later she is reunited with GaoLing. The two "sisters" immigrate to America separately and marry a pair of brothers, Edmund and Edwin. LuLing's second husband dies from a hit and run accident when Ruth was two years old.

Ruth struggles growing up as the child of a single parent who believes in curses. Once Ruth learns the details of her mother's past, she gains a new understanding of her and her seemingly erratic behavior. Answers to both women's problems unfold as LuLing's story is finally revealed in its entirety