A family’s mentally ill son buys a gun with the intent to perpetrate a massacre. Prior to this, he’d planned on doing it with a knife.
Note that they can’t get their son institutionalized, even though it’s apparent that he’s dangerous. Clayton Cramer in his book My Brother Ron: A Personal and Social History of the Deinstitutionalization of the Mentally Ill discusses the changes in America’s mental health system that has led to dangerously violent people wandering around free until they finally do something that will get them incarcerated.
Kudos to the parents. By age 21 I would imagine the daily grind of dealing with a mentally ill son would have worn most people out.