Sergeant Xu Dahu broke several major cases, but his independent style led to conflicts with his supervisor, Li Pengfei, and he was transferred. Dahu resigned in frustration but was encouraged by his girlfriend, Ho Yuk-kam, to start a private detective agency. While taking the police officer's exam, Ho Zi-wai became friends with Li Chang-zi, who was frequently praised and promoted. Zi-wai felt unfairly treated and eventually left his job to join Dahu's detective agency. While investigating a kidnapping case, they discovered more secrets and illegal activities involving Pengfei. They used a citizen's arrest empowered under Article 101 of the Criminal Procedure Ordinance to bring the culprit to justice.
Grand Preceptor Shen Qian colludes with the nomadic Nu Muqi tribe to divide and conquer China. When the tribe attacks Yunzhong City, Emperor Xian sends Luo Zeng to resist them. However, Shen tricks Luo and he gets captured. The Emperor mistakenly believes Luo betrayed him, executes his whole family, and Luo's son Luo Kan, along with his brother, escapes and seeks help to save their father. Three women who once rejected Luo Kan's advances also join forces to assist him. However, they are captured, and Luo Kan and Luo Cang lead the people of Yunzhong to fight the invaders. They succeed in defeating Shen Qian, and Luo Zeng demands that he testify to Shen's treachery. Shen's son plots to overthrow the Emperor and imprisons him in a tower. He and his allies, with the help of Luo Kan and Luo Cang, rescue the Emperor and confront Shen.
Zhan Meng-bai's father is assassinated by a mysterious archer, and his love interest is killed by the same assassin. Determined to avenge them both and discover the archer's secret, Meng-bai meets his supposedly deceased mother and many other renowned martial artists. Meanwhile, he falls in love with the daughter of the leader of the Emperor's Valley. Eventually, Meng-bai learns the identity of the archer and learns that the archer intends to die in battle with him.