The movie begins in the year 2005, where two high school student are extremely sad because they missed their school prom. The two students are Schmidt, who is rejected by a girl and Jenko, who has been barred due to his low grades. But these two students destinies collide once again after seven years when they meet at the police academy. The two are given a task of high school infiltration and they have to attend the school as students.
They are given new identities and are given the task to contain the spread of a drug named HFS. Based on their high school grades, Jenko has to take arts and Schmidt had to take Science classes, but these two exchange their identities and they move forWard in their mission. The rift arises between them and they bring their grudges in between their work. But they finally succeed in their mission of finding out the suppliers.