Story : In this episode of Superquark, the documentary from the BBC Planet Earth series focuses on fresh water, our most precious resource, which constitutes only 3% of the planet's water. The directions in which it falls or flows determine the distribution of life forms on Earth. The cameras will follow the course of rivers, from their sources to the sea, exploring waterfalls, canyons, lakes and swamps, with their fauna and incredible landscapes, shaped and brought to life by water. Incinerators, regasification plants, TAV... The planet of protest and protest against major works (the so-called NIMBY, "Not in my back yard") which, at least in theory, should promote the development of the country, in the report by Lorenzo Pinna and Vanessa Strizzi. Alberto Angela and Michelangelo Pepe will accompany us in the exploration of Castel dell'Ovo in Naples. It only seems like an ancient fortress, but in reality it holds 2700 years of history.