The series begins with the arrive of spring in Moominvalley. Moomin, along with Little My, Moominpappa and Moominmamma wake up in Moominhouse, while Snufkin also comes back from his south travel on the first day of spring. The first eight episodes create coherent storyline that is based on the third novel, Finn Family Moomintroll. During the story, Moomin and his friends find out the magical silk hat, that turns out to belong to the Hobgoblin. He later gets his hat back from the Moomin family. The Moomins later find a wrecked boat, fix it and travel to a lonely island which is full of Hattifatteners. Next, two small creatures called Thingumy and Bob with a large suitcase arrive to the Moominhouse, and they are followed by the Groke. After the Moomins manage to evict the Groke from their way by giving her Moomin's seashell, it turns out that Thingumy and Bob are keeping the large "King's Ruby" in their suitcase. After Thingummy and Bob return Moominmamma's missing handbag, the Moomins celebrate the event with a large junket, where suddenly the Hobgoblin also arrives. Finally the problem of the King's Ruby's ownership is solved with the Hobgoblin's magic. Moomin takes place between a three-year period of time. Moomin and his family or friends manage to take part in two winter periods through the series, although the Moomins are normally supposed to fall into hibernation. Through the series, Snork, the Snork Maiden's inventor brother, designs and creates two flying ships of different type; the first is destroyed due sabotage and the second one gets finished at the end of the series. Before the second winter period, the Moomins and their friends also get to know Alicia and her grandmother, who is a witch. She teaches Alicia to become a real witch and has a negative opinion about the Moomins and their nice nature. As the series goes on, the witch however begins to appreciate them. At the end of the series, Snork decides to go on a journey with his finished flying ship while Alicia and her grandmother also leave the Moominvalley for the third winter period. The series concludes when the winter arrives, the Moomins fall into hibernation and Snufkin travels to the south once again.