Far in the depths of space is lost the small planet Erlit, which is inhabited by the remains of the once powerful and civilized race. Despite the small population, violent internecine wars shake it. At certain intervals, the sinister red star Caroline approaches Erlita at a dangerous distance. These encounters are always accompanied by attacks of Base mutants, scouring the universe in search of survivors, over whom they conduct a swap of terrible experiments. And here's the sinister Caroline again approaching . Will the survivors be able to organize a worthy rebuff to the invaders?