Moomintroll, as you know, spends the entire winter in hibernation - which means he is no different from any other Moomintroll. But in the spring, when he wakes up, he is not even averse to doing something unusual. For example, climb a mountain in the company of your friends Snufkin and Sniff and discover at the top a hat forgotten by someone - a black top hat. And it turns out that this hat can work wonders! With its help you can defeat the Antlion and ride on cute clouds, but there is one problem: you never know what the hat will do next time. Maybe we should get rid of it? But, as it turned out, it is not so simple. And the main magic will begin when the real owner of the hat appears in Moominvalley... The book you are holding in your hands is a real event. For the first time in many years, the entire series about the Moomins has been re-translated into Russian! Those who are already familiar with the inhabitants of Moominvalley will be curious to take a fresh look at their adventures. And those who are about to meet the fairy-tale world of Tove Jansson for the first time can only be envied in a good way!