Ji-Sook, a department store clerk, is drowning in despair and her father’s crushing debt. When a mysterious offer arrives from Suk-Hoon—a powerful man with a dark agenda—she is lured into assuming the identity of her wealthy lookalike, Eun-Ha, who has died under mysterious circumstances. Stepping into Eun-Ha’s privileged world, Ji-Sook becomes the wife of Choi Min-Woo, a chaebol heir haunted by paranoia and emotional instability. The glittering life, however, comes at a steep price. As Suk-Hoon pulls the strings and secrets begin to surface, Ji-Sook is forced to live a dangerous lie under constant watch, all while falling into a complicated and fragile relationship with Min-Woo. With every step deeper into deception, Ji-Sook must choose between protecting the truth or protecting herself.