|Assassination Plot Arc|
|Starting Date||October 4, 2007|
|Ending Date||February 28, 2008|
|Number of Chapter||19|
← Escape from Zhao Arc
Training Arc →
Assassination Plot Arc is the 4th story arc of the Kingdom manga.
After the Keiyou Campaign, a disturbance in the palace was created with the assassination of 15 men who held political power within the Ei Sei Faction. The assassins belonged to five clans, the Gouma, Kensen, Kakuriki, Shukyou, and Shiyuu. It is revealed that Kyou Kai is a member of the Shiyuu clan and is involved in the plot to assassinate the king.
Shin was summoned to the royal palace, as a last resort to provide protection for the king. While Shin fought the Kensen clan, Kyou Kai saved Ten by killing the Kakuriki clan with ease. Shin arrived at Ei Sei's chambers and they attempted to escape through a secret tunnel. However, the door was locked on the other side and the Shukyou clan emerged along with Kyou Kai.
Kyou Kai engages Shin in a one on one duel and demonstrates a superior swordsmanship derived from the Shiyuu's Priestess Dance. However, she seems reserve, as if she didn't really want to fight Shin. At that point, the Gouma Clan arrived at the same time as the Shukyou leader decided Kyou Kai was not the true Shiyuu.
As the Gouma launched an attack, Kyou Kai teamed up with Shin and asked him to buy her 30 seconds. Shin managed to somehow provide that time for her to rest and after that, Kyou Kai performed the dance and killed quite a few enemies, until she collapsed leaving three Gouma and one Shukyou left standing.
As they went for the King, the Royal Guards and retainers arrived, killing the remaining assassins. Shin convinced the guards to leave Kyou Kai alone and treat her wounds instead, claiming that she helped protect the king.
As her injuries were being taken care of, it was revealed that Kyou Kai is actually a woman. Once she regains consciousness, Kyou Kai escapes the palace but is caught on the walls by Ten. In a brief chat, Kyou Kai reveals her tragic past as a member of the Shiyuu clan and how she desires to avenge her sister's death.
- Shin is promoted to a 100-Man Commander.
- King Ei Sei faces an assassination attempt.
- Kyou Kai's origins, background, and technique are explained.
- Various assassin clans are introduced.
- Kyou Kai demonstrated unreal level of swordplay that suppress common sense and later revealed to be a woman in disguise.
- Ryo Fui is revealed to be the mastermind behind the assassination plot.
- This arc was not shown in Anime as it was skipped entirely but instead was replaced by Kyou Kai's backstory, her reason for vengeance, and the first appearance of the Ryo Fui Faction.
- This arc is completely skipped in the anime, instead with Ryo Fui stating that he would not have cared if the king died durring his brother's rebellion when he was introduced.