The story is set in the Qing dynasty during the reign of Emperor Yong Zheng. Yong Zheng's harsh and brutal policies lead to widespread discontent and dissension. Meanwhile, a secret death squad, named after their dreaded weapon — the flying guillotine — goes around slaying the emperor's enemies. The young crown prince, Hong Li, disguises himself as a commoner and embarks on an inspection tour to Jiangnan. There, the prince evades assassination attempts orchestrated by nobles plotting to seize the throne, and uncovers a shocking truth about his birth and origin. Besides, he also meets and befriends two maidens, Lu Si Niang and Yu Niang.