In the twenty-second century Earth obtains limitless, free energy from a source science little understands: an exchange between Earth and a parallel universe, using a process devised by the aliens. But even free energy has a price. The transference process itself will eventually lead to the destruction of the Earth's Sun—and of Earth itself. Only a few know the terrifying truth—an outcast Earth scientist, a rebellious alien inhabitant of a dying planet, a lunar-born human intuitionist who senses the imminent annihilation of the Sun. They know the truth—but who will listen? They have foreseen the cost of abundant energy—but who will believe? These few beings, human and alien, hold the key to Earth's survival.

Safe in his Scriptorium, Brother Léon dreams of discovering sapientia: perfect knowledge. On opening an Arabic tome brought by his brother-in-law Stefan the Bastard to the Monastery of St. Maurus, Brother Léon sees an unknown numeral: 0. In the 13th C world of universal belief, his faith crumbles - why has God granted such knowledge only to the Infidel?A group of unwanted peasants are sent to help the monks with the construction of the Cathedral of St. Catherine. Guy has no thoughts beyond a life free from hunger, until the night they arrive at the monastery and his brother Henri collapses and soars to the Battlements of Heaven. He returns bearing God's command to bring all home to Heaven, and so begins his silent preaching through the town. As her spires rise to challenge the Heavens, the Cathedral of St. Catherine touches all who move in her shadow. A new statue of the Archangel Michel strikes terror in the townsfolk, for they believe the statue was finished by an angel as the mason slept. Banished by the Abbot to the cathedral roof, St. Michel is joined by his colleague Death, (recently returned from stress leave). They guide the events unfolding below them, as the death of faith, belief, knowledge, of loved ones, and of the world as it is known spreads through the town.Unlike his fellow monks, Brother Valerian is at ease moving between monastery and town. A descendant of Vikings, he remains untouched by the superstitions surrounding the new cathedral. In contrast, Audrey, a daughter of the tavern owner, remains drained of emotion after the death of her fiancé and unborn child. She sees only the cathedral's destructive miasma, the people it has killed and maimed, and what it has stripped from the town.Charged by the Abbott to write a tome detailing the construction of the cathedral, Brother Léon struggles not only with his loss of faith but also with writer's block. He blames his brother-in-law Lord Stefan for bringing evil into the monastery. Meanwhile, Stefan the Bastard plays Abbot, family and king against each other, wanting only to return home to be with his wife. The Abbot sees enemies in everyone as he readies the cathedral for its royal consecration. Guy seeks a life free from living in Henri's shadow. Escape from the past seems possible, until familial ties plunge him into a darker world.