The setting: The city of Shumballa, in the land of Kush, which lies south of Stygia, in the vast grass lands. It was the capital of Kush, the population of which was composed of black people, brutal and warlike, known as Gallahs; they were ruled by a caste of dusky aristocrats, known as Chagas, who claimed descent from a band of Stygians who long ago wandered southward and set up a kingdom, of which Kush was the remnant. There were only a few hundred of these, but they maintained their position by intrigue and ferocity. 

The people: The mad, degenerate king of Kush; his handsome, cruel, sensual sister, Tananda; Tuthmes, a rebellious nobleman of royal blood; Diana, a Nemedian captive; Agara, a fanatical Gallah witch-finder; Conan the Cimmerian. 

The plot: A commander of the Gallah warriors, a black man, having incurred the displeasure of Tananda, was cast into prison, in the upper room of a tall tower. He awoke in the night, to be murdered by a pig-like monster which had scaled the tower-wall and torn the bars from the window. This monster was a survival of a forgotten age, controlled by a dusky adventurer from Kordafan. An hour later the body of the commander was discovered, and a man ran to Tuthmes, to tell him of it. From the marks and prints, it was evident that no human being had killed the commander. Tuthmes told the man that the time was ripe to stir up the Gallahs against the king and his sister, and told him to find Agara, the black witch-finder, and hint to him that Tananda had had the commander murdered. Tuthmes then went upon his roof, to brood over the walled city and the myriad mud huts of the Gallahs spreading into the plains beyond the wall. He, himself, had sent the monster to murder the commander in order to throw suspicion on Tananda, who was the real ruler of Kush. He plotted the overthrow of the ruling dynasty and the making of himself king, with the aid of the Gallahs. But it was a risky task, for the Gallahs had been murmuring, feeling that a pure black king should sit on the throne of Kush. Tuthmes sent for a white woman to present to the king, plotting to effect his ruin through her. His emissary bought a Nemedian girl, Diana, from a Shemitish slave-trader, who had captured her from an Argossean trading vessel. 

Shortly thereafter Tananda were riding through the city outside the walls, which was known as Punt, when Agara appeared and stirred up the people against her. Her escort were murdered, and she was dragged from her saddle and stripped naked by the mob, who were about to tear her to pieces when she was rescued by Conan, who had just arrived in Shumballa, a wandering adventurer who had recently been a corsair. She had the captain of the guard speared by his own men, and made Conan captain. Shortly thereafter he put down a rising of the blacks, and was greatly esteemed by the king. 
Diana was brought to Tuthmes, who gave her her orders and sent her to the king; but Tananda had her kidnaped, and Conan, seeing her, became vastly interested in her. 

Agara, by his magic had discovered Tuthmes’ part in the murder of the black commander, and accusing Tuthmes, was by him seized and tortured to death – or so Tuthmes thought. Tuthmes, seeing that he could not overthrow the king as long as Conan lived, sent his Kordafan monster to murder Conan. 

Tananda ordered Diana to tell her the details of Tuthmes’ plot, but the girl refused, for Tuthmes had frightened her almost into insanity. Tananda whipped her, and Conan entered and put a stop to it. Tanada in a fury threatened him, and he laughed at her, and taking the girl, went to his house. 

In the great square of the inner city, a sorcerer was being tortured, while a great mob looked on and jeered. Conan, attacked at his house by the monster, wounded it mortally and pursued it into the square, where it rushed to its master, the Kordafan, and fell dead. The frenzied mob tore the Kordafan to pieces, and then appeared Ageera, who denounced Tuthmes. He was likewise slain by the mob, and then the blacks rose and destroyed Shumballa, and Conan and Diana escaped.