Queshao and Bobby are saints? Two officers from the Tropet Police Department. On a mission, Queshao and Bobby met a group of aliens. After listening to the introduction of aliens, Queshao and Bobby realized that they were an investigation team sent by aliens and came to the earth to mix with local residents for ethnic sampling. When aliens come to the earth, they sometimes dress up as civilians and sometimes pretend to be policemen to understand human life on the earth, which makes the local police in charge of the search task very difficult. To this end, Que Shao was jailed for accidentally hurting his own strength. Soon, Queshao escaped from the police station under the cover of a nun. After escaping from the brig, Queshao vowed to find these changeable and mysterious aliens. After a series of ironic misunderstandings, Queshao discovered in a confrontation between the police and aliens that these aliens are most afraid of water. So Queshao skillfully led other companions to attack the mysterious whisperd with water, and finally expelled them from the earth.