Les Ardoines ,a Breton island : the wells run dry,the fog invades the land ,the population is about to leave for the mainland;Fabrice urges them to fight,they build a pump :irrigation is possible again.But they run into difficulties ,the island is in debt ,and whereas many opt for the mainland,some of them ,led by Fabrice leave for Doucemer (=Sweetsea). In Doucemer,the inhabitants extract iodine ,a substance used for medicines ,from the seaweeds;the island thrives and soon becomes a tourist region . Fabrice does not want to become a person of private means;he buys a tiny island ,Medusa.