Planet Rakhat of the Alpha Centauri system. The world of a mysterious ancient civilization. The world to which the first expedition of earthlings, sponsored by the Vatican, went, and on board the starship there were not only a doctor, an engineer and an astronomer, but also four Jesuit missionaries. Of all the members of the expedition, only one returned to Earth - the young Jesuit Emilio Sandoz, who experienced all the horrors and humiliations of captivity and slavery on Rakhat. From now on, his only goal is to stay as far away from the hostile planet as possible. However, the Jesuit general spares no effort to return Emilio to Rakhat...