Ted Kaczynski sent the FBI on a $50 million manhunt. We investigate how his childhood as a prodigy led him to academic glory at Harvard.
Soviet leader Joseph Stalin concealed Hitler’s body from the West for decades. The FBI spent years tracking false leads and sightings of Hitler. Only in the 1990s did Russians open archives to reveal a handful of Hitler's teeth and fractured skull pieces.
Police closed the case of the infamous Boston Strangler when Albert De Salvo confessed to the grisly murder of 13 women. But recent forensic evidence reveals the Strangler could still be at large.
In 1918 Russia's last imperial dynasty, the Romanovs, were assassinated. But doubts remain as to whether all members of the royal family were put to death. Did the Tsar's daughter, Anastasia, escape?