While Hercules and Iolaus rescue a woman, who is being harassed by a gang of men, Gladius is preparing to go back into the arena to fight against a lion. The woman tells Hercules and Iolaus that her husband is a slave in Apropus. Hercules is shocked to find they allow slaves. The woman tells him "Not officially, but Menas Maxius is the richest man in this area and he does what he wants. He promised to set my husband free, then didn't. Now he's banished me from the land." Iolaus asks why she would want to return and she replies that her husband has never seen his son. Hercules and Iolaus decide to go with her to Apropus.
Back at the arena, Gladius returns to his cell wounded after killing the lion, Leutis tends his wounds. Hercules tells Iolaus he is working on a plan to help free the slaves. The woman, Felicita, sees Maxius' guards up ahead and informs Hercules, he tells her to go back and wait in the inn that they passed earlier. The guards ask the two men for twenty dinars toll to pass by them, Hercules proceeds to beat up the guards and accomplishes his plan of getting them sent to prison.
Once in prison, the two men set about finding Gladius, meanwhile the slaves are put to work in the quarry. Hercules finds Gladius and tells him he has news from Felicita, but he refuses that he has a wife. In the cells, Hercules discovers that Gladius was told that Felicita died in childbirth. Meanwhile, Felicita is caught attempting to sneak back into Apropus. At the arena, Maxius changes the rules telling the crowd that the men will no longer fight animals, but each other, to the death. Hercules is put up against Skoros, Hercules tries to tell Skoros that they do not have to fight and they can stand together against Maxius. They fight and Hercules knocks him unconscious and tells Maxius "I donât kill for pleasure! I donât kill for sport! And Iâll burn in Hades before I kill for your amusement!" with this act of defiance, Maxius orders his guards to kill Hercules.
As the guards fire arrows at Hercules, he blocks them with his spear. Maxius' wife, Postera orders them to stop and bring Hercules to her chambers. She tells Hercules that she wants him as a personal slave, Hercules refuses saying, "Iâd rather sleep in a dungeon with rats-- than share satin pillows with a viper." She tells him he will get his wish after he is given forty lashes for his insolence. After his whipping, Hercules is taken to the tombs, where he can sleep with real vipers.
As the crowd at the arena, prepare for the next couple to fight, Leutis knocks Gladius out and takes his place in the arena. As the two men fight, Gladius wakes up and Iolaus tells him that Leutis is fighting in his stead. Leutis manages to beat the other man and as the crowd encourage him to kill the other man, Leutis knocks him unconscious with the butt of his sword. He thrusts the sword into the ground and refuses to kill the other man and that he agrees with Hercules that they are not animals to be used in sport. Postera orders them both killed.
The two slaves are brought back to the cells and strung up as a warning to anyone else thinking of defying Maxius. When Hercules is brought back to the cells, he sees the men and cuts them down, ordering the guards to bury them properly. With Hercules returned the guards then take Iolaus. Hercules tells Gladius about his wife and son waiting for him outside the city and convinces him they are alive. Hercules says he can see them when they find a way out of the prison.
The guards come and tell Hercules and Gladius they are the next two to fight. Hercules tells Gladius they need to stand together and fight Maxius' men and together they can make a difference. As Hercules and Gladius enter the arena, Gladius notices Felicita being held captive by Maxius' guards. Postera tells Gladius that if he refuses to fight, then Felicita would go back to her old life, and his son would become her personal slave. Hercules reminds him about what they had talked about in the cells, and they need to pretend to fight, Gladius says he cannot take the chance and the two men begin fighting. Hercules tells Gladius he cannot trust Maxius or Postera saying, "They lied, before. Whatâs different now?" Gladius manages to knock Hercules to the ground, Hercules throws his sword and tells Gladius he is through with fighting and Gladius need to decide who will control his life. The crowd begins chanting for Gladius to kill Hercules.
Gladius takes his sword and throws it into the chest of one of the guards, Hercules joins him in his fight against Maxius' men. They get the keys from the guards and set the other slaves free and they join in the fight. As Maxius is attempting to flee, Hercules throws his sword and catches Maxius' clothing. He tells him to call off his men. As the guards drop their weapons the prisoners pick them up saying, "We'll see who dies now!" Hercules stops them saying there will be no more blood shed and Maxius will set them free. Gladius is reunited with Felicita and his son.