Rustem of Kerakek, a physician from Bassania, is summoned by Shirvan, the King of Kings of Bassania, after being wounded with a poisoned arrow. Rustem saves his life and helps reveal that it is the king's son who was behind the assassination attempt. Shirvan rewards the doctor with the promise of raising him to the priestly caste and making him a court physician. However, Shirvan first commands Rustem to go to Sarantium to act as his spy. He leaves behind his two wives and their children, a baby girl and a seven-year-old boy named Shaksi who is suggested to have unusual powers of perception. Shaksi's premonitions later compel the family to depart from Kerakek and follow Rustem to Sarantium.