The mysterious statues of Easter Island, the Moai, were built by one of the world's strangest and most isolated civilizations, the Rapa Nui. Today, new evidence reveals why they were built and what caused Easter Island's sudden downfall.

New evidence gives rise to speculation over whether Attila the Hun, one of history's fiercest warriors, played a role in the downfall of the Roman Empire by waging a campaign of terror. This investigation centers on Trier in Germany.