It would seem that it could be simpler and more boring than putting things in order in the archive? This is exactly what the cadets of the School of Interworld Control of the Borderland Lenya Letun, Vova Zaikin and Vasya Palyanytsya thought, who were sent to the World of Magic to serve their sentences. But even in such a simple matter, the guys managed to find adventures on their own. The serpent Kalinich, whom the cadets met in the magical World, suggested that the work could be done faster if they found a certain book with magical formulas in the basement of the archive. But instead of the book, the guys stumble upon the dungeon of Lednitsa, the granddaughter of Chernobog himself, and set her free. After twenty years of a quiet life, the Miras again found themselves on the brink of disaster. Now, in order to save them and avoid punishment for their misconduct, the cadets and the Serpent set off in pursuit of an ancient creature. But it was not to be: the sorceress Vasilisa Ivanovna the Wise opens a hunt for the guys from the Borderland and their winged three-headed friend... An amazing and exciting story about incredible dangers and amazing feats in a magical world full of magical and fairy-tale creatures - in the new novel “Three of casket and the Serpent Kalinich to boot" from the master of the fantastic genre Sergei Derkach.