Shinchan and the Kasukabe Defense Force are going to experience school life in "Private Tenka Unification Kasukabe Gakuen" for a week. Student with high elite score during this trial enrollment will be admitted as a scholarship student. Although Kazama dreams to attend this elite college with the Defense Force, he has a quarrel with Shinchan and dashes out the dormitory. When he was found by the Defense Force, his intelligence had been reduced and his butt had a strange bite mark. Who is the suspect? In order to find out the truth, "Kasukabe Detective Club" is formed!