Joseph Mengele experimented on adults and children in the Auschwitz death camps. He was a prime target and was, for many years, the world's most wanted criminal. The Hunters were Simon Wiesenthal, the U.N. War Crimes Commission and even Mossad. But none of them succeeded. The method Wiesenthal used to track Mengele was the following up of disparate clues, no matter how obscure. He would scour newspapers from all over the world, looking for unusual names, or sightings of possible Germans in unlikely places, such as small towns in South America. He suspected he was being sheltered by a well funded Nazi organization - and he was right. Throughout years of chasing, Mengele always got away. He drowned in Latin America in 1979.