Since the 1920s the Belgian factory Gevaert accidentally disposed tons of silver as a by-product of the production of photographic film. This outflow ended up in the nearby Grensbeek (Border Creek). Over a period of almost fourty years, a former tool worker at the factory managed to recover a large amount of the wasted metal by draining the stream and moving the sludge to a local metallurgical plant where the silver was extracted. It earned him a decent living wage. This story fascinated Lucas Leffler, who took the position of a researcher. He found archives, newspaper clippings and historical documents, and photographed the factory and the creek. But he also took sludge from the bottom of the Zilverbeek, trying to find traces of silver, just like the pioneer before him.