在戒备森严的紫禁城，有按照十二生肖命名的大内密探，负责保卫皇上的安全，他们个个身怀绝技，其中武艺最高的当属灵灵虎和灵灵猪，唯独灵灵狗不会武功且整日沉迷于科技发明。为此，他未来的老丈人梅大侠和丈母娘林美人非常嫌弃，总想悔婚，但是未婚妻梅希望却对他一往情深。皇宫内，皇上正与丽妃卿卿我我，一群蒙面刺客闯入，随着皇上的一声呼喊，大内密探现身救驾，却中了调虎离山之计，幸好还有灵灵狗，他虽然不会武功，但凭借发明的各项武器，成功地击退了刺客。沉迷于发明的灵灵狗不解风情，梅希望想勾引一个男人气气他，阴差阳错救了前来刺杀曹公公的袁若男。皇帝和皇后准备为彩云公主挑选十全驸马，曹公公趁机派人参加，想借机谋取皇位。灵灵狗和灵灵虎也参加了，一场更大的阴谋即将在皇宫上演…

In the heavily guarded Forbidden City, there are secret agents named after the twelve zodiac signs, responsible for protecting the safety of the emperor. Linglinghu and Linglingpig have the highest martial arts skills, but Linglinggou does not know martial arts and is obsessed with technological inventions all day long. For this reason, his future father-in-law Mei Daxia and mother-in-law Lin Meiren are very disgusted and always want to regret the marriage, but his fiancée Mei Hope is devoted to him. In the palace, the emperor was flirting with concubine Li when a group of masked assassins broke in. Following the emperor's cry, the inner secret agent appeared to rescue him, but he fell into a trick to divert the tiger away from the mountain. Fortunately, there was Linglinggou, although he would not Martial arts, but with the various weapons invented, he successfully repelled the assassins. Linglinggou, who is obsessed with inventions, is puzzled. Mei hopes to seduce a man to anger him, but accidentally saves Yuan Ruonan who came to assassinate Eunuch Cao. The emperor and the empress were going to select the perfect son-in-law for Princess Caiyun. Eunuch Cao took the opportunity to send people to participate, hoping to take the opportunity to seize the throne. Linglinggou and Linglinghu also participated, and a bigger conspiracy is about to be staged in the palace..