The Black Stone. 1926: Curtis and Lawrence try in vain to recover the black ivory, but the Road to Kor is closed to them thanks to Ibn Saud, the new master of Arabia. Meanwhile, in Soviet Ukraine, Itzhak fights alongside the partisan anarchists, and then flees to Siberia. He moves along the Tunguska River, on the same track followed seventeen years earlier by Rasputin, with Baron Sebottendorff on his trail.