Summary
Highlights
As Gu Beichen, the protagonist cleverly intervenes in a plot where Gu Qingyao is framed for poisoning Gu Baiwei's snacks. By using his intelligence and the 'Detective Gu Renjie' persona, he exposes the maid Bilian as the culprit, who, under pressure, reveals Gu Baiwei's manipulative tactics. This act prevents Gu Qingyao from being unjustly punished and marks the beginning of Gu Beichen's efforts to protect his sister.
Gu Beichen continues to actively protect Gu Qingyao from the mistreatment of servants and the explicit favoritism shown by his mother, Princess Consort Xu, towards Gu Baiwei. He confronts his mother and father, highlighting the injustice and the damage it causes to the family's reputation. He successfully reclaims power over household affairs and assigns it to his wife, Yingluo, significantly disadvantaging Gu Baiwei and elevating Gu Qingyao's status.
The family prepares for Grandmother's 70th birthday. Gu Baiwei attempts to use Gu Qingyao's culinary skills to present a gift, secretly hoping to take credit. However, Gu Beichen, aware of the original plot, ensures Gu Qingyao's direct involvement in preparing the special birthday cake and candles, garnering sincere appreciation from Grandmother and foiling Gu Baiwei's scheme. Grandmother's favor towards Gu Qingyao grows due to the medicinal diet she had been receiving, unaware it was from Qingyao.
During the birthday celebration, Grandmother suddenly collapses, poisoned. Gu Qingyao is immediately blamed. Gu Beichen, convinced of his sister's innocence and her medical prowess, allows her to intervene. Qingyao successfully diagnoses and treats Grandmother, saving her life and proving her capabilities. This incident further discredits Gu Baiwei and strengthens Gu Beichen's resolve to protect Qingyao.
Gu Beichen intensifies his investigation into Grandmother's poisoning. Through clever manipulation and prior knowledge of the plot, he exposes Granny Zhang as the first conspirator and then unmasks Granny Yu as a secret agent from the Northern Di, a princess name Helian, who conspired to replace Gu Qingyao with Gu Baiwei to destabilize the Zhenbei Royal Family. The family is shocked by the revelation, and their perception of Gu Baiwei completely changes.
With the Northern Di conspiracy exposed and Gu Baiwei's treachery revealed, the family begins to reconcile with Gu Qingyao. Her mother expresses deep remorse, and her father offers his full support. Even her once-antagonistic brothers apologize. Gu Beichen provides Gu Qingyao with unique skills and advice, empowering her to navigate her new life. Later, Prince Jin is appointed commander-in-chief against the Northern Di, taking Gu Qingyao with him due to her knowledge of the region and medical skills.
The protagonist settles into a comfortable life, managing his household and enjoying his relationship with Yingluo. The military campaign against the Northern Di, led by Prince Jin and aided by Qingyao, achieves significant victories. Amidst this peace, Yingluo reveals she is pregnant, bringing even more joy and stability to their lives. The protagonist reflects on his successful transmigrated life, having fulfilled his mission of changing Gu Qingyao's fate and securing his family's future.
The protagonist finds himself transmigrated into a novel, not as the hero, but as Gu Beichen, the villainous heir apparent of the Zhenbei Royal Family, responsible for destroying his entire family. He quickly realizes the tragic fate of his legitimate sister, Gu Qingyao, who is unloved by her family and pushed towards a path of darkness by the manipulative fake daughter, Gu Baiwei. The protagonist vows to change the dire future prophesied in the novel.