Of course, since childhood, Vovka and Seryoga knew that it was wrong to torture animals, but for the sake of a scientific experiment, you can put a cat in a fountain, nothing will happen to it! And that some old woman is shouting that the cat will soon take revenge on them and is mocking them to his heart’s content - so how can one seriously believe in this nonsense? But what is it? First, the friends simultaneously dream about a cat turning into a human, and then this werewolf from a nightmare... appears in their classroom at the teacher's desk! “Has the old witch’s prediction really come true?!” – the boys think with horror, and that’s when the cat teacher tells them...