Female assassin Ren Ru Yi, the former left envoy of the Scarlet Guards, becomes a member of the Wu's State's escort delegation to save the King of Wu who has been taken hostage by the State of An. Together with Ning Yuan Zhou, the leader of the Wu State's Six Realms Hall, the free-spirited Yu Shi San, Princess Yang Ying, clever teen Yuan Lu and the imperial guard Qian Zhao, they experience love, life, death, and grow together.