The first strike of the bell warns the residents of Rogonda that the Black Hour is approaching, by the second strike everyone rushes home, locks the shutters and doors, and with the third, the Night Birds fly into the city and Darkness comes. Nobody knows what happens to those who did not manage to get into the shelter before this time, they simply disappear...Masha has already visited five worlds, and in each of them she made an important discovery that greatly helped their inhabitants. And all because Masha Nekrasova is Skvoznyak, that is, “a wanderer passing through the fabric of the worlds,” which means traveling along the Great Spiral and saving worlds is her mission. And since she ended up on the fishing island of Rogonda, something is clearly going wrong there and her help is needed. But first we need to find out why the city residents are afraid of the Night Birds and the Lighthouse Keeper, what is hidden behind the Darkness that comes with the third strike of the bell, and who are the sea bodies that everyone talks about only in a whisper?