I am here again, in this obscurity with words. Now, without you, I am darkness and I am words. This is way this novel begins, with the letter that Alejo writes to his distant beloved. The moment of writing the letter is the best in the days of the protagonist, occupied nearly completely, in the caring of the so numerous elderly and is also occupied in “rising” the tower in which they live. The Humanity eventually defeated Death, finding out the clue in the final moments of the decrepitude of people, who instead of dying, and after a short and transitory process, they live practically for ever. But some time ago a cosmic cataclysm stopped the earth rotation and its inhabitants have to re-create days and nights with the use of huge machinery that transports whole cities through the border-line between light and darkness to keep the circadian rithms, which their lives have been built with, do not collapse, not to be destroyed.