After bungling their latest assignment, goofy undercover cops Jesus (a blonde haired Anthony Wong Chau-sang) and Ken (Sam Lee Chan-sam) are assigned to infiltrate a Catholic girls' school. Their assignment: find the student who made off with a knapsack full of money that Jesus lost track of during the operation. Jesus assumes the persona of Father Gum, the new moral science class teacher, while Ken tries to pass himself off as May, a deformed schoolgirl. Teacher Maggie Leung (Rachel Fu Tin-wing, speaking a combination of Mandarin and heavily accented Cantonese) and student Candy Tong (Gillian Chung Yan-tung) are prime targets for observation but Ken receives some unexpected distraction when both Candy and another classmate fall for "him."