Documentary video maker Robert Stone is a lot more evenhanded than Oliver Stone when it comes to weighing the evidence we have about the assassination of John F. Kennedy and the role of Lee Harvey Oswald. But he has little to add to common knowledge about this subject, apart from shooting down or dismissing most of the conspiracy theories that have found some favor with portions of the public at one time or another. Among the many talking heads who tell this storyincluding Edward Jay Epstein, Todd Gitlin, Tom Hayden, Mark Lane, Priscilla Johnson McMillan, Norman Mailer, Dan Rather, and Josiah Thompsonit’s ultimately Mailer who takes the lead, furnishing the film’s title while explaining how and why the lone assassin theory makes the most sense to him. 90 min. (JR)