The story follows Feng Yu Ji, a woman living under an assumed name, who returns to the Shen household disguised as her twin sister – the Shen family’s young mistress – in an attempt to avenge her sister. She befriends Shen Tan Qian, the son of a wealthy merchant, and begins to investigate the truth behind a long-suppressed murder case, ultimately revealing the true culprit and bringing them to justice. Throughout this journey, Feng Yu Ji and Shen Tan Qian move from mutual mistrust to open honesty and, ultimately, find healing in one another. With courage, wisdom and the strength of their self-sacrificing love, they bring the truth to light. As the truth unfolds, their joint efforts also put an end to the Shen family’s opium trade with the Japanese, gradually bringing an end to the city’s opium addiction and ushering in a new era of science and civilisation.