Watch The Great American Serial Killer for Free: How to Stream the Movie Online at 123Movies. . In the early 1990s, Robert Kemp savagely raped, tortured, and murdered thirty-two people before being caught and sentenced to death. The Great American Serial Killer is the account of the final interview by Dr. Jeremiah Stone. Kemp's story, in his own words, lets us all see into the mind of the twisted and sadistic mind of a true psychopath.