Deep at the bottom of the sea, some 3,800 metres below the surface of the freezing Atlantic Ocean, lies the wreckage of a ship now stripped of its former glory: it is the unmistakable carcass of the Titanic, once man's grandest mechanical achievement. Almost one century later, modern treasure hunter Brock Lovett and his crew dig for answers, intrigued by the ocean liner's sunken hidden riches. But when lively centenarian Rose Calvert, one of Titanic's few survivors, learns about the ambitious crusade, the ship's never-before-heard story unfolds. And as the white-haired guest takes an emotional trip down memory lane, Rose intertwines the fate of King Louis XVI's exquisite Heart-of-the-Ocean diamond with a passionate romance aboard the ill-fated Titanic. However, history gives answers only to those who know how to ask questions. Is Lovett on the verge of making an extraordinary discovery?