Late at night, a mix-up at a hotel front desk—assigning the wrong room number—unexpectedly uncovers the mystery behind the fatal fall of a genius young pianist. Gu Yue is reborn, returning to the very eve of the tragedy, only to discover that her best friend and her husband have conspired to frame her. She attempts to rewrite her destiny, yet surveillance footage vanishes and evidence is fabricated; every clue points to a motive of "jealousy and betrayal." The strangulation marks on the victim's neck and the missing musical score expose the dark secrets of a wealthy heiress. This is a tale of vengeance spanning two lifetimes. The truth proves sharper than death itself.