do you mean , dad , like a mysterious lagoonin the south american jungle that has lain undiscovered since the beginning of time and only now in the late nineteenth century has professor challenger stumbled upon it , always suspecting , of course , that it was there but never being able to prove it until one day in december 1899 , disregarding the scoffing and the mockery of the london science society , he leads an unlikely but intrepid team of master geographers , veteran adventurers and eccentric aristocrats in a crazy canoe expedition up the piranha infested waters of an uncharted tributary of the river amazon where they chance upon the fleeting form of a fleeing native who they follow through the crocodile infested swamp until he leads them to where they part the curtain of a dense thicket of mangroves and lianas and come face to face with the uncannily still black waters ofa hitherto uncharted lake the size of an inland sea which contains in its deceptively tranquil depths the living forms of prehistoric submarine creatures that were previously thought to be extinct ?