History's Greatest Mysteries season 4 episode 9
Episode title: Decoding the Mysterious Antikythera Mechanism
An ancient mechanical device found on a 2,000-year-old shipwreck has become known as the world's first computer. The machine is centuries more advanced than historians thought possible, but its origin and true purpose are shrouded in secrecy. Can modern technology finally unveil what the mysterious Antikythera Mechanism actually is?
