Two girls in 19th-century China are kept in isolation by their families, but form a close bond with each other, communicating by secret messages in their own invented language. In the present day, their descendants were once childhood friends, but now struggle to keep in touch in light of the responsibilities of their busy lives. Drama, starring Gianna Jun and Bingbing Li in dual roles.

A story set in 19th century China and centered on the lifelong friendship between two girls who develop their own secret code as a way to contend with the rigid cultural norms imposed on women.