Today, both high school and junior high school students often ask their teachers and parents questions about black holes. This book is addressed mainly to children 10–12 years old. After reading it, inquisitive schoolchildren will learn a lot of interesting things about extraordinary space objects, which are sometimes called “invisible”, “monsters” or simply “horror”. The knowledge gained will be useful when studying natural sciences at school. Recommended by the Moscow Planetarium. Illustrations by Ksenia Larichkina