Tianjing University girls' dorm is in chaos. Someone has been stealing underwear, and the university has proved itself completely incapable of solving the problem. So the girls have decided to take action on their own. Under the leadership of An Jing, an 18-year-old resident of the dorm, they want to create a dorm patrol to catch the thief. But there is one big problem. As per university rules, the dorm patrol needs an official faculty mentor, and no one wants to take on the job. Without any other recourse, the girls ask Professor Li Wei, a genius physicist, to be in charge of the patrol. Li Wei is a man who is peerless in the theoretical world but completely useless in the practical one. He also happens to be An Jing's brother-in-law. Will this group of female vigilantes and their mentor catch the thief? Will Li Wei prove an asset or a hindrance? Will the girls finally have peace, or will their operation cause more chaos?