Jest rok 645 naszej ery, kiedy cesarz chińskiej dynastii Tang, Li (Seong-woong Park) wyrusza na podbój koreańskiego królestwa Goguryeo. Niepokonana armia cesarza zdobywa fortecę za fortecą, niebezpiecznie zbliżając się do stolicy. W jednej z krwawych walk ginie brat wojownika Sa-moola (Joo-hyeok Nam). Sam Sa-mool zostaje awansowany przez króla i przydzielony do wykonania tajnego zadania. W ostatniej stojącej na drodze do stolicy twierdzy Ansi rządzi generał Man-chun Yang (In-seong Jo). Król ma z nim na pieńku i wcale nie zamierza mu pomagać. Wręcz przeciwnie. Zamierza wrócić z pozostałościami wojska do stolicy i tam przygotować się do ostatecznej bitwy. Sa-mool ma przeniknąć do Ansi, zamordować generała i też pognać z jego wojskiem w stronę stolicy, zostawiając Ansi na straty.
This story unfolds 8 years after 'Battle of Hwangsanbeol', which destroyed Baekjae, when Silla-Tang Dynasty union attacks Goguryeo.
Set in the 7th century AD during the Korean peninsula's division into three perpetually warring kingdoms, Once Upon A Time In A Battlefield focuses on the Shilla's king Kim Choon-chu efforts to conquer his rivals: Koguryo and Baekche. To achieve this goal, he allies with mainland China's Tang empire, the superpower of the era, and together the two polities plan to attack first the weakest Baekche at its main fortress of Hwangsanbul, guarding the only easy access to the mountainous interior. But the fortress commander General Kye Baek (Park Joong-hoon) will be resisting to the end...This comedy relays on clash between ancient time and modern language combined with irony and distance to the war.
Seol Hie loses her parents and eyes to the murderous brutality of General Woo Shin-tak. She trains herself in swordsmanship and martial arts for the next two decades before setting out to even the score with Woo.
A wonderful time travel exploring. The Kingdom of Goguryeo. Oh! Goguryeo!, Oh! Balhae! A travel to find the warmth of ancient history with Do-Ohl Kim-Yong-Ok, A representative philosopher of our modern age! We couldn't help but crying when we saw the towering Heul-Seung-Gohl-Seong, the first seat of government of Ju-Mong, through out the celadon-colored sunrise... From the top of the Mt. Baek-Du to Manchuria, The Scent of Goguryeo and Balhae that has been scattered all over the wild field wake our hearts up from a long, deep sleep!