Shen Su rushed back joyfully to attend her sister's wedding, but unexpectedly found that her sister had been murdered. She swore to find out the truth.
From the diary left by her sister, Shen Su saw that her sister had discovered the Xu family's secret. She guessed that her sister's death was most likely related to this secret. Therefore, she decided to marry into the Xu family by taking her sister's identity.
At the wedding banquet, she found that everyone in the Xu family was very strange: her husband Xu Yiyang was at odds with his stepmother, Xu Yiyang's sister was full of hostility towards her when she saw her, and Xu's younger brother secretly threatened her. Everyone in the Xu family was full of doubts, and Shen Su's investigation officially began.
By chance, Shen Su overheard Xu Jiarou (Xu's sister) making a phone call and mentioning the night when her sister died. Shen Su immediately suspected that Xu Jiarou was the murderer. She observed secretly, wanting to find evidence.
Xu Jiarou was a famous singer and was invited to a charity dinner. Shen Su unexpectedly found that Xu Jiarou was lip-syncing. On the night of the dinner, Shen Su took pictures of the evidence of Xu Jiar…
