Maw, a Myanmar engineer, has been promoted to Deputy Head of Production, bringing along his younger sister Sin to work in the same factory under the supervision of Nui, the Quality Control Manager. The promotion and Sin's arrival create suspicion among some factory employees, including Wit, Head of Production Line A, who has been at odds with Maw throughout their working relationship. A tense atmosphere blankets the entire factory, intensifying several times over on the first night of these changes, leading to a mysterious murder case that claims the life of Saw, Maw's close friend, who disappears into the shadows. To uncover the truth, Inspector Narong leads his team to work the case, investigating to find out... who is the killer?

927 AD. The Killer-Blade Army has toppled the ruling dynasty, plunging the kingdom into chaos. The only remaining heir, Prince Jung-Hyun is living in exile, unaware of his family's dark fate. Still loyal to the dynasty, the beautiful and deadly warrior Soha sets out to find Jung-Hyun and guide him to become the great leader he was born to be. But with the Army's greatest assassins and the criminal underworld hunting them, Soha and Jung-Hyun are swept into an explosive, non-stop battle of swords, wits and bloodshed as they fight to reclaim the fallen throne.