It's no big secret that twelve-year-old Hannes is in love with his classmate Carolin, who he compares to a beautiful white cloud in the sky. But when Carolin spends most of her time exploring the village's history with Benno, Hannes becomes increasingly jealous of his rival. The only person who is happy about this situation is Kerstin, who is in fact interested in Hannes. In order to impress Carolin, Hannes takes her and several others out for a boat ride in the nearby Bay of Greifswald, but his plan takes a deadly turn as a storm approaches.

Based on the children's book with the same name by Klaus Meyer.