The Moomin family gets stranded on an lonely island and spend the night on a makeshift tent during a thunderstorm. At night, a horde of Hattifatteners swarms the tent and in the morning Snork Maiden has a really bad hair day.
The storm has passed and the Hattifatteners sailed away, and the Moomin family is enjoying a sunny morning at the beach. Before they all head home, it's time to go on a adventurous treasure hunt.
Late fall brings cold, rain and mushrooms to Moominvalley. This year it also brings two visitors: temperamental Little My and her peculiar friend Ninny, the invisible child. Only Moominmamma can find a way to help make Ninny visible again.
Hemulen feels it's his duty to wake up the sleeping Moomin family to prepare for a Christmas Eve. None of the Moomins have never heard of such celebration, but soon feel the spirit of Christmas next to a beautifully decorated tree.
Moomintroll wakes up from his winter sleep, even though the winter still holds sway over the Moominvalley. While bravely exploring the beautiful valley, he hears whistling. Could it be Too-Ticky and his invisible mice?
It's the middle of cold winter but Moomintroll is awake, caretaking the Moominhouse and feeling very lonely. Also awake is a mischievous Little My, looking for a perfect snow sledge, and Too-Ticky, mainly relaxing in the bathing hut.
It seems as if time has stood still in Moominvalley and even the sun has gone away. Moomintroll, Too-Ticky and Little My witness something beautiful and terrifying: the Lady of the Cold. Just don't look into her eyes.
Too-Ticky will light a large bonfire during a full moon. The plan is to lure the sun back to the sky. Moomintroll is excited, as are the other children of the winter. There's also one unwanted guest: The Groke. Will the sun rise?
The winter days passed slowly. After sneaking into Too-Ticky's bathing hut, Moomintroll finds one his ancestors: the cupboard troll. There are other winter guests, too. The Moominhouse is a warm place for everyone, and full of jam.
The sound of a loud horn can be heard when the healthy Hemulen skis into the Moominvalley. The ever energetic Hemulen needs a lot of fresh air and exercise, showing everyone how to ice swim and ski in style. Moomintroll is less impressed.
Moominhouse has many visitors, since food is scarce this cold winter. A small dog Sorry-oo arrives and soon also meets Healthy Hemulen and Too-Ticky. Sorry-oo dreams of wolves and some howling can be heard from the Lonely Mountains.
The sun is shining, the snow is melting and Too-Ticky turns her cap inside out. All signs that spring is coming. The skating season is also over, as Little My learns when she gets stranded on the ice. Moominmamma wakes up.
When Too-Ticky is playing his barrel organ, you know the spring is here. The whole Moomin family is awake and the children are paying a surprise visit to Fillyjonk, who has predictions of a terrible catastrophe.
On one beautiful day, Moomintroll catches a little dragon from a pond nearby. A new pet, or so he thinks, since the smoke breathing creature seems to only like Snufkin. Well, and flies.
