According to a legend that dates back to the 16th century, a cache of Incan gold worth hundreds of millions of dollars is hidden off the coast of southeastern Brazil. It's known as the "Treasure of the Trinity," and it's eluded all who have sought it for 500 years. But a modern-day team of explorers follows a radical new theory to uncover its whereabouts: a remote, treacherous island where thousands of deadly vipers roam. On the expedition to Queimada Grande -- known to locals as Snake Island -- the team is armed with advanced technology to unearth complex clues and decipher puzzles that have protected the treasure for centuries. This Discovery series takes viewers along on the epic journey to one of the most dangerous places on Earth.