It is the true story of mathematics and economics genius John Nash and his terrible struggle with paranoid schizophrenia. He has delusions of a roommate at Princeton (where he is attending graduate school) and his niece as well as an F.B.I. agent that is supposedly making him a code-breaker to save the world from a nuclear attack in the early '50s. His mental illness is made apparent to him when a psychiatrist takes him to an asylum and gives him electric shocks to try to eradicate the delusions. He has a lifelong struggle and becomes a threat to others. He starts to teach at Princeton still is suffering. He wins a Nobel Prize in 1994 for an economic theory he materialized in the late '40s while he was attending graduate school. It really makes his delusions seem like real people so you can see what schizophrenic people really think is real and their inability to discern reality from imagination. It is a very touching movie as well as a little sad to see this guy suffer so much.