Continuation of the adventures of the legendary Calculator, the unique mathematician Erwin Kahn, on the planet Abyss. Sentenced to exile in the disastrous Sargasso swamp, he survived and returned - of course, not to hide in a hole. His weapon is intelligence, but any weapon is meaningless if it has no use. Will the exorbitant risk stop the Calculator, who cannot imagine himself outside the Great Game? What should he choose: to live his life calmly and unnoticed on a peaceful planet or to find an unsolvable problem and... solve it? For Erwin there is no question...