Goryeo-Khitan War

Queen Dowager Cheonchu wishes her own son to become the next crown prince. However, Mokjong is not happy with how Kim Chi Yang, the Right Senior Executive, and Queen Dowager are trying to take over his place as he is determined to succeed the throne to King Taejo's descendant. Therefore, Mokjong is about to summon Prince Daeryangwon back to the palace, while Kim Chi Yang and Queen Dowager secretly send assassins to murder him. 

Court Lady Choi threatens Prince Daeryangwon to take the food Queen Dawager has prepared for him. Prince Daeryangwon quickly runs away from the temple and hides himself in Mount Samgak. Court Lady Choi orders the men to burn down the mountain to find him. Meanwhile, Mokjong holds a banquet for his people, and Kim Chi Yang plots a crime for the night.

Kang Jo, Northwest Temporary Government Officer, sets off for Gaegyeong with a crucial mission. However, deep within his thoughts, he grapples with the realization that Goryeo's very existence is at stake if the current state of ruling persists. Meanwhile, in another part of the kingdom, Prince Daeryangwon anxiously awaits assistance from His Majesty. To his surprise, he finds himself confronted with an entirely new chapter of life, carefully orchestrated for him.

Caught in the crossfire between those gearing up for war and those working to prevent it, the puppet king, Wang Sun, and Kang Gam Chan form the front line of those seeking to avert conflict. On the opposing side, Kang Jo believes in the inevitability of war and sees it as a chance to eradicate the Khitans. The turning point comes when envoys from Khitan arrive with a message poised to alter the course of history. 

The Khitan emperor is about to lead a large army and cross the Yalu River to attack Goryeo. 

The battle between Goryeo and Khitan begins in the middle of the night, and the people of Goryeo shiver with fear. With 400,000 soldiers, Khitan attacks Heunghwajin for seven days straight, but they are unable to destroy the fortress. Therefore, they come up with another strategy. Meanwhile, Prince Daeryangwon visits the temple where people are gathered to pray. 

The Emperor of Khitan is infuriated as he loses the first conquest expedition he is leading. He starts advancing south with his army towards Samsuchae to destroy Goryeo's main force. Therefore, even though Officer Yang manages to defeat Khitan soldiers, the main force assumes Heunghwajin has lost the battle as they are trapped. Officer Yang must find a way to send the word. 

The spearhead commander of the Khitan army launches an attack and captures Kang Jo. The emperor of Khitan threatens Kang Jo and the captured generals to become vassals of Khitan. Meanwhile, Hyeonjong receives the news that the Goryeo army was defeated, and Deputy Minister Kang advises him not to share the news with the people.

Hyeonjong sends Deputy Minister Kang to Khitan's camp as an envoy to relay his message. However, the commander of Khitan's army does not trust his words and decides to hold him back in their camp. Furthermore, Deputy Mayor Won of Seogyeong Fortress gives up on fighting against Khitan and is about to surrender.

Deputy Minister Kang successfully deceives the Emperor of Khitan and returns to Gaegyeong to relay the news to Hyeonjong. However, the chancellors are not pleased as they believe he took the chance to negotiate with the Khitans. Meanwhile, Gwakju, Yeongju, and Sukju have fallen, and the Khitan army is on their way to seize the Seogyeong Fortress.

Despite Kang Gam Chan's plea, Wang Sun stands firm, refusing to abandon the fortress and his people.

Alone in Gaegyeong, Kang Gam Chan makes the fateful decision to buy precious time for Wang Sun's escape. 

Wang Sun experiences emptiness upon realizing the hardships faced by those south of Gaegyeong.

Seeing his people turn against him, Wang Sun feels shame for not being the emperor they needed. 

Wang Sun arrives at Gongju, where he is welcomed by its governor and one of his daughters.

Yang Kyu, fully aware that this might be his final battle, throws himself into the Khitan army to rescue prisoners.

Despite facing opposition, Wang Sun is determined to reform the fundamental issue that has plagued Goryeo.

Despite facing fierce resistance, Wang Sun, alongside Kim Eun Boo, continues to pursue his plans. 

The queen consort seeks to punish Kim Eun Bu while the king is away from the palace. But guilt leads Kang Gam Chan to attempt to spare the commander. 

With Kang Gam Chan's help, Wang Sun succeeds in launching reforms. However, the local governance is unhappy, and Kang Gam Chan faces the consequences. 

Wang Sun meets with the local officials for reform, and Kang Gam-chan returns to the capital. Khitan sends an envoy, demanding Goryeo pay their dues.
 

Khitan demands part of Goryeo's domain. The royal court is torn between prospects of war and annexation. Kim Eun-bu faces a crisis and plans escape.
 

Wang Sun declares war. Kim Eun-bu fights to relay Khitan's internal affairs to Goryeo. Kim Hun and Choi Jil stage a protest against the gentry.
 

Kang Gam-chan gains commander experience in the fight against Jurchen. The king offers his amnesty to the protesters, but the leaders remain militant.

Kim Hun and Choi Jil begin their rebellion on the grounds of retrieving land. On Wang Sun's order, the border guards race to Gaegyeong to rescue him.

Amidst death threats against court officials, Kim Hun and Choi Jil pressure Wang Sun to take back his army. Kang Gam-chan devises a counterattack.

Wang Sun captures rebel mastermind Park Jin and leverages the friction between Kim Hun and Choi Jil. Khitan's emissary makes threats of war once more.

Under Wang Sun's orders, his court officials prepare for extermination. The king arrives at Seogyeong to meet the rebels, but his military is absent.

Wang Sun subdues the rebel forces and prepares for war against Khitan. Kang Gam-chan leads Goryeo's army to the battlefront as commander-in-chief.

Khitan charges south, avoiding Goryeo's main forces. Despite this turn of events, Wang Sun refuses to flee and remains steadfast in the capital.

Wang Sun takes position in the palace with his army, court and people. Kang Gam-chan confronts Khitan as they flee northward. The battle begins.