Upon learning of her daughter's promiscuous ways, Mrs. Dubois (CARRIE FISHER) sends Sue off to a mental hospital and wants to take legal action against Mark and his single father, Mr. Deloach (JOE MANTEGNA). Yet, the later uses his Marine connections to have his boy sent off to boot camp rather than face possible prison time. Before that occurs, however, Mark and his friends visit Sue where Mark meets her roommate, Dori Lawrence (RACHAEL LEIGH COOK), a movie actress and performer suffering from schizophrenia.

Mark has little time to think about that, however, as he soon finds himself at the mercy of tough Marine drill instructor Skeer (VAL KILMER) on Paris Island. Learning of the boy's past indiscretions, Skeer sets out to make Mark's life a living hell, but the latter perseveres and eventually thrives under the strict discipline. Drawn to Dori, he visits her whenever he's on leave and the two soon become an item. Her unstable condition, however, results in relapses as well as others questioning Mark's influence on her. From that point on, he does what he must to prove his love for her.