On one tragic night, murder and betrayal took place in the royal palace. Amidst the blazing fire, two sole survivors escape, with one badly wounded. Following their order, they seek help in the Red Lights District from a famous Gisaeng, asking for aid and shelter. Who are they? Just what happened? Ten years later, with a new Emperor on the throne, this section of the city is still as busy as ever and appears to be relatively calm and normal... However, beneath all that, in the villagers' hearts, the dissatisfaction for the Emperor rises... with their only hope and support being their secret hero, "Crimson Moon." Just who is he? Why is he the rebel's leader? And what happened to the victims of that night ten years ago? As these mysteries slowly unravel, the secrets from the past and the event that took place ten years ago slowly resurface once again...