A vast sandy beach, metre-high dunes and a rich flora and fauna – all this characterises Spiekeroog. Here, pioneer plants help to protect against flooding and sandbanks free of human activity help to protect seals. Every year, this so-called "green" East Frisian island attracts up to 100,000 visitors. Yet, this island, located in the Wadden Sea National Park, has fewer than a thousand inhabitants. Among them are a beach researcher, a conservationist, and a astrophotographer: author Herbert Ostwald accompanies them and other islanders on their adventures amidst sand, storms, and tides.