Lencois, located in northeastern Brazil, is known as the whitest dunes on earth. However, when the rain comes every half year, this scenery of pure white sand stretching over 150 thousand hectares completely changes. Countless lagoons are formed, creating a startling contrast between the white sand and blue water. Even fish suddenly appear in these lagoons. Where do they come from? Through a year-long coverage of Lencois, this episode reveals the truth about this surreal nature's beauty.