The Seal of Sanderoog

12-year-old Milla moves with her mother Maren to the island of Sanderoog. Maren has got a job there as director of the spa. She is expected to lure more tourists to the island - if necessary, even at the cost of nature protection. Milla, too, has problems of her own: on her first day at her new school she clashes with Henry, the "leader" of the class and son of the powerful Hajo Ehlers who is inundating the whole of Germany with his "shrimp bars" and thus making other fishermen redundant. Moreover, Ehlers is keen to take over the premises of the seal shelter where he wants to build a wellness and casino complex. To this end he bribes and charms all and sundry - with the exception of Maren. One day Milla and her friends find a newborn baby seal that has lost his mother and seems condemned to die of starvation. They name the little seal "Button-Eye", take him to the seal shelter and ask the director Dr. Justus Reinders to give him a chance. He can't say no to the children and accepts "Button-Eye". But only on one condition: Milla has to take care of the seal around the clock. Will Milla and her friends be able to save the seal shelter from the profiteering Ehlers? In this difficult situation Ehler's son Henry, of all people, proves to be a great help...