When an ambitious young woman, Han Ji-eun, agrees to a fake marriage with the cold and reclusive CEO, Lee Jae-han, to save her family from financial ruin, she expects a simple transaction. The arrangement is foolproof: a beautiful, fake life in exchange for a desperately needed fortune. All they need is one perfect Christmas photograph to seal the deal.

But as they play the part of a loving couple, the lines between their staged romance and their real feelings begin to blur. Ji-eun finds herself drawn to the haunted man behind the CEO's mask, a man burdened by a secret grief. In a reckless attempt to understand him, she uncovers a six-year-old truth that shatters their contract and exposes a web of lies, betrayal, and a cover-up that goes all the way to the top of his powerful family.

Suddenly, their fake marriage becomes a dangerous quest for justice. With a powerful enemy against them and a love that was never part of the deal, they must decide if the truth is worth fighting for, even if it means losing everything.