In this episode, Waldemar Januszczak explores the architectural and artistic legacy of the early Islamic world, challenging the notion of the Dark Ages by highlighting the sophisticated engineering and aesthetic achievements of the era. From the precise calculations of the astrolabe to the intricate geometry of the Dome of the Rock and the innovative water management systems of the Kairouan mosque, the film reveals how Islamic civilization fostered a period of profound cultural and scientific advancement. Through a journey across historic sites, Januszczak illustrates how these structures were not merely functional, but served as profound expressions of faith, geometry, and a vision of paradise.