From the assassination of Abraham Lincoln to John F. Kennedy, Dr. Ronald Feinman discusses the dark history of threats and assassinations against U.S. presidents. Feinman also discusses little known assassination plots such as the almost successful attempt on the life of Richard Nixon. Also discussed are threats that were not successfully carried out, including threats against President Obama. He also comments on popular conspiracy theories related to the JFK and RFK assassinations, and the attempt on the life of Ronald Reagan.