故事发生在乾隆时期的一次洪水，灾难发生地的父母官李满仓却不去救助百姓，反而贪污，导致这里民怨沸腾，乾隆亲自带着御前侍卫前来调查，当场就要将李满仓给斩杀了。却殊不知一个巨大陷阱正在等待着他。左匡父亲因为在抗倭之中被奸臣杀害，而不知情的他一直认为是昏君乾隆所为，听闻乾隆来到这里就伺机刺杀，最终刺杀失败，但也得知了父亲被杀真相，反而做了乾隆的御前侍卫。这场天灾害得很多人流离失所染上了疫病，幸亏神医吴道春研究出了医治的房子，但李满仓为得到药方竟然派人刺杀吴道春，幸亏被人所救，乾隆此番出京危险重重，前有李满仓，后有倭寇山口太郎虎视眈眈个个将目标对准了乾隆皇帝，御前侍卫是否能保护乾隆安然无恙呢......

The story happened during a flood during the Qianlong period. Li Mancang, the parent and official of the place where the disaster happened, did not go to rescue the people, but was corrupt. He personally brought the imperial guards to investigate, and Li Mancang was about to be beheaded on the spot. Little did he know that a huge trap was waiting for him. Zuo Kuang's father was killed by treacherous ministers during the anti-Japanese war. Without knowing it, he always thought it was the work of the faint emperor Qianlong. He heard that Qianlong came here and waited for an opportunity to assassinate him. In the end, the assassination failed. Became Qianlong's imperial guard. In this natural disaster, many people were displaced and contracted the disease. Fortunately, the genius doctor Wu Daochun developed a healing house, but Li Mancang sent someone to assassinate Wu Daochun in order to get the prescription. Fortunately, he was rescued. There is Li Mancang, and later there is Japanese pirate Taro Yamaguchi, all of them aiming at Emperor Qianlong. Can the imperial guards protect Qianlong safe and sound..