At the birthday banquet, Old Madam Shen Peilan accidentally overhears the inner voice of the beggar girl A Ning, learning that she is her long-lost biological granddaughter. The wet nurse Zhou Yun swapped the children, colluded with the adjutant to kill A Ning's parents, plotted against Shen Peilan, and schemed for the Shen family's property. Relying on the inner voice, Shen Peilan investigates and discovers the truth, exposes the trick of blood paternity testing, relies on Western testing to obtain evidence, and punishes the villains. True heiress Shen Anning returns to the family, the grievances of the Shen family are redressed, and the two young women put aside their prejudices to support the Shen family together.