Executive Producer: Gene Roddenberry
Producers: Gene L. Coon + John Meredyth Lucas
Associate Producer: Robert H. Justman
Script Consultant: D. C. Fontana

Story by: John Kneubuhl
Writers: Gene L. Coon and Gene Roddenberry
Dir.: Ralph Senensky

Captain Kirk: William Shatner
Science Officer, First Officer, Cmdr. Spock: Leonard Nimoy
Dr. Leonard "Bones" Mc Coy: DeForest Kelly
Lt. Sulu: George Takei
Lieutenant Commander Montgomery Scott: James Doohan
Lieutenant Uhura: Nichelle Nichols

Captain R. M.. Merik: William Smithers
Claudius Marcus: Logan Ramsey

Stardate: 4040.7

The Enterprise and her crew find the wrecked S. S. Beagle. Now Kirk, Spock and Dr. McCoy decide to investigate on 892 IV in hope to find out what happened to the crew. On the planet they discover signs of civilization (smog a. o. ) which reminds them to 20th century earth. The first people they meet are poor people, led by a man called Septimus, who are fleeing from others. The fugitives warn the Enterprise people to hide themselves. The "sun – worshippers", as they are called, are pursued by a group of armed soldiers and caught by them.

In the city, all resembles life in ancient Rome, if there were not the broadcasts, adverts and technology of the 20th century. The people are entertained by circuses, like in ancient Rome: People fighting each other to death. Septimus is not fighting. He meets his death declaring he is objecting violence and stands his point. Kirk, Spock and McCoy meet the former captain Merik of the Beagle, who is now called Merikus. He tells them that he was forced by the planet's premier, Claudius Marcus, to order his crew down on the planet to fight and die in the arena. By that he has not only saved his life, but gained a status as First Citizen in society. Merik and Marcus now try to force Kirk to do the same. When given the communicator to call his people down, Kirk orders strictly that no one beams down onto the planet. 

As a consequence, Kirk is bound to be executed and Spock and McCoy are to fight in the arena. Scotty faces the problem of finding a way to act, while he not even knows what is wrong down there, and to not interfere with the culture, according to the First Directive. McCoy pretends to be sick, while all three try to escape from the cell with unbreakable bars. This does not work and Kirk is locked up separately. Now Spock tests the strength of the bars even more regularly and the worried Dr. McCoy confronts the Vulcan with his speculations about Spock's attitude towards life. Both wonder how their captain is doing and both know that the other worries, too. 

All worries of the planet's leaders seem to circle around the public favor of the various TV stations. It is only shown what pleases the audience: Violence. In order to stay on top of the programs more and more fights are arranged. Spock and McCoy get two opponents in ancient Roman arena fighting style and try not to harm the others though they are technically better of. When Spock uses the Vulcan neck pinch, a faulty play is announced and the program is cut off with the promise to air the sequel later. They still try to convince Kirk to order his people down. When Scotty cuts off the electrical power (which as he explains is not a violation of the FD) for a moment, Kirk uses the chance to free his friends. Merik has suffered from his deeds and does not want to see history repeat itself; he gives Kirk a communicator to contact Scotty for their rescue. Knowing what he had risked, Merik is stabbed by Claudius Marcus. Back on board Uhura clearly states the pursued people were Son worshippers and Kirk realizes the equivalent of the early Christians in them.