Like the very center of darkness, the gloomy Vranov Tower stands in the deep taiga. None of those who tried to find her came back. Only a guide who has the key is able to cross the border and lead his companions to the goal, but aren’t they all heading towards certain death? Three girls - the daring Elsa, the capricious Lika and the timid Marfa - are not at all alike. But it was not in vain that fate brought them together, because each of them has special abilities and each has to pass its own test and find a way through the darkness.