The Karavec race have used the power of gnaris to travel vast distances across the universe, and have populated sunless worlds, including Arion and Hikon. They are led by Barrow, the Great Savant of the Karavec. When all the embryos in the Regional Embrycultural Centre on Arion are murdered and their blood stolen, Barrow calls upon the human, Jim Forster, to investigate the crime. Their search for answers takes them to another Karavec world, Hikon, in the solar system of Ogien, where they intercept an unexpected audio signal from a neighbouring planet called Ziemia. Many strange events happen on Ziemia as they seek the perpetrator of the crime known as the Saviour.