In her search for her mother's story, islander Helma Petersen stumbles upon a long-kept family secret. When Sönnich Petersen dies, no one in the village on the Sylt mudflats is sad, least of all his daughter Helma. He was not a loving father, the war had made him hard. His death comes at a time when the emerging tourism brings new people and customs with it. More and more islanders want to share in the prosperity, and Helma soon rents out to bathers. But there is something else that concerns her: her mother, who died at an early age, was always kept silent. There is also a secret about the mother of her childhood friend Rudi, she was picked up during the war and never came back. How could the two women disappear just like that? Why didn't anyone ask about them? Helma searches for clarity and comes across the island's dark past ...