The book is not just another science fiction novel, it is designed to evoke a burning desire to change your life, reconsider your daily, established priorities and think about the values for which we live. The destinies of a variety of characters: people from the future and the present, the dead from the past, angels and servants of Lucifer intertwine and merge together on Earth, in Purgatory, in Hell and the heavenly City. Humanity, like Sodom and Gomorrah, rapidly degraded, mired in sins, neglecting moral standards and drowning out the voice of conscience, desperately trying to reach us. Already in 2099, the concept of love - the most “powerful” word in the Universe - disappeared from the face of the Earth. No one knows what this feeling is, why it is needed and what its purpose is. The old grandfather-scientist, a fanatic of the past, must have time to dictate a will to his grandchildren Denis and Arthur, to tell how, with the help of a crystal heart, to rid the world of emptiness, dullness and selfishness. The brothers will not just travel through time, they will find themselves in the epicenter of human lives, on their paths will be victories and defeats, temptations and betrayals. Which of the brothers will give his soul to the Devil, having received limitless power over human life, and which will take the side of Light and the fighter for eternal values? Will the servants of Lucifer, who know all the “pain points” of the human soul, allow us to win the next round in the eternal confrontation between Good and Evil and return boundless sacrificial love to humanity? There will be no sweet happy ending. After all, a book is not our illusory desires, which we strive for all our lives and cannot achieve. The book is a reality, subject to the laws of the just and selfless Creator of the World, and not to the norms and foundations of modern society.