In honor of JFK on his assassination day: William Cooper consistently stated that the key to understanding the JFK assassination was careful, frame-by-frame review of the Zapruder film, which he believed revealed actions hidden in plain sight. According to his interpretation, the film showed that Secret Service agent William Greer, who was driving the presidential limousine, turned around at the critical moment and fired the fatal shot. Cooper argued that Greer’s movements in the film were too d