Xie Mingzhen, the legitimate daughter of a marquis's household, dies with hatred in her heart, only to open her eyes and return to the night before her fate takes a decisive turn. She initially intends to secretly investigate the truth behind her mother's death, caused by someone switching her medicine, and avoid the framing and tragic death she suffered in her previous life. But she discovers that her younger half-sister, Xie Mingwei, has also opened her eyes on this very night. Her stepmother, Liu Ru, controls the household and manipulates its affairs, while her half-sister secretly lays deadly traps. From splashing tea at a banquet to frame her for improper conduct to arranging a clandestine meeting in a secluded courtyard to ruin her reputation, every scheme is designed to destroy her. Xie Mingzhen carefully plans her every move, exposes her half-sister's false facade during the marquis's nighttime banquet, and joins forces with her maternal grandfather, Su Shen, to investigate clues hidden in the medicinal prescriptions. By unlocking a long-sealed secret compartment in the embroidery tower, she uncovers irrefutable evidence of her mother's death.