A team of Secret Service officers, historians and forensic scientists unravel the mysteries behind some of the most high-profile deaths and assassination attempts in the White House. The 1881 shooting of James Garfield prompted Alexander Graham Bell to invent a metal detector in order to locate the assassin's bullet and try to save his life. Zachary Taylor's body was exhumed to determine if he had been poisoned instead of dying from gastroenteritis. An assassination attempt on Franklin D. Roosevelt helped shape the function of today's Secret Service. And a plot to crash a passenger jet into the White House in order to assassinate Richard Nixon was foiled.