Mike Wilson, a young police officer, poses as a student under the alias Tony Baker and thus infiltrates a high school in order to investigate a narcotics ring. He lives in an apartment with Gwen Dulaine, a married woman who pretends to be his aunt in public but attempts to seduce him in private. "Tony" flirts with pupil Joan Staples and incurs the wrath of teacher Arlene Williams as he makes acquaintances in school. He discovers that Joan uses marijuana and inquires about where she purchases it. He ultimately learns that a mysterious man known only as "Mr. A" is the one who sells drugs to the students, helped by an assistant called Bix. With help from an undercover cop, Quinn, who risks his life to save Mike's, the criminals are apprehended and Joan promises Mike that her drug use is over.