In 19th-century China, when wives and daughters were foot-bound and lived in almost total seclusion, the women in one remote Hunan county developed their own secret code for communication: nu shu, women’s writing.

With the arrival of a silk fan on which Snow Flower has composed for Lily a poem of introduction in nu shu, their friendship is sealed. As the years pass, through famine and rebellion, they reflect upon their arranged marriages, loneliness and the joys and tragedies of motherhood. The two find solace, developing a bond that keeps their spirits alive.

But when a misunderstanding arises, their lifelong friendship suddenly threatens to tear apart.