Before submarines were invented, they were imagined. It took hundreds of years for the impossible to come true. But people finally made a ship that could move under water. It took years to solve the problems of supplying air, keeping water out, rising and sinking, and seeing where to go. But Jules Verne imagined ways to solve all of these problems in "Twenty Thousand Leagues Under the Sea". This is the story of the amazing submarine, The Nautilus, launched by Captain Nemo over 100 years ago.