Otto always has a runny nose. Compared to other children, Otto is a bit smaller and somewhat weak-chested. So his parents decide that Otto should recover during a children's holiday by the sea. Otto is not thrilled at all: a summer without parents – unimaginable. He is supposed to make friends, but he doesn't know the other kids at all. And the camp leader, Ms. Felgenkranz, also makes him uneasy. But then he gathers all his courage and suddenly finds joy in digging in the sand, swimming, and eating fish. And a friendship or two also develops. Otto never thought that a vacation without his parents could pass by so quickly.