This picture book tells the story of worry, the dark shadow that lingers in our minds. Worries, both big and small, come at us unexpectedly. Some fade away quickly, while others grow more serious over time. How can we shake off that persistent feeling that tightens our chest, disrupts our lives, and tries to take control? In this story, an unknown "worry" comes to visit the protagonist. Despite all efforts to get rid of it, the worry clings on stubbornly and refuses to let go, growing larger and larger, almost as if it's going to swallow the protagonist whole. Through reading, children will naturally learn wise ways to handle and manage their worries.