You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

Category: AMERICAN HISTORY 
Clue: On June 21, 1982 he was found not guilty by reason of insanity in the shooting of President Reagan
john hinckley

Category: WHAT SHOULD I "DU"? 
Clue: A philosophical system that seeks to explain all phenomena in terms of 2 distinct principles
dualism

Category: CINEMATIC CHICAGO 
Clue: Say the name of this Chicago-set 1992 horror movie 5 times into a mirror & a "sweet" killer will appear

candyman