The film revolved around Jim Garrison (played by Kevin Costner), the New Orleans D.A. who believed there was a conspiracy to assassinate Kennedy and a cover-up that stretched to the highest levels of government.

• 影片以新奥尔良检察官吉姆·加里森（由凯文·科斯特纳扮演）认为肯尼迪案件属于谋杀，并且以政府最高机构遮掩此事的故事情节为线索。