The last of the "barbarians", William Harrison, was killed by Claudius in the arena. However, later Merik says that those of his men who adapted are still alive.
Apparently Proconsul Claudius Marcus is tougher then he looks. According to the opening newscast, he's the one who killed the last "barbarian," no more then six year previously and probably more recently.
A few episodes earlier, in "Patterns of Force," Spock claimed the odds of another planet developing a culture like Nazi Germany were "virtually impossible." But here he has no problem accepting a culture identical to Earth's ancient Roman culture, right down to the same names of the deities.
Given that they state very clearly what the Prime Directive is, how they're sworn to die before violating it, etc., they take Spock down without any head covering of any sort. Clearly their mission is going to require them to contact some people at some point, but wouldn't Spock's obvious pointed ears be a dead giveaway they're not from the planet?
Also, the landing party is wearing their usual uniforms, though it was established in previous episodes that they are able to synthesize any local clothing they require.
Rome did have a sun god named Mithras (the Greek form of the Persian name Mithra). Presumably Spock and the others didn't know that although it seems a bit odd Spock wouldn't remember it.
Why doesn't Scotty lock on to the landing party and beam them up? Once Kirk calls him he's got a pretty good idea of where they are, and it shouldn't be hard to locate Spock in any case on the sensors.
Kirk blasts McCoy's and Spock's cell door open with a machine gun but when he opens the door there are no bullet marks on it.
For the first but not the last time, Kirk doesn't have the landing party injected with subcutaneous transponders like they did a few episodes earlier in "Patterns of Force." This would seem to be a necessity on any covert mission where they may not be able to use their communicators, and when even if they die the Enterprise might have to recover their bodies (particularly Spock's!) to avoid a Prime Directive violation.
Despite the fact their on a covert meeting where they're not supposed to violate the Prime Directive, the landing party takes the more obvious Type II pistol-phasers rather then the compact, concealable Type I Is.
We hear about "Hodgkins' Law of Parallel Planet Development" but it still seems unlikely that this planet is going to have the same names for its deities as Earth's ancient Rome.
Marcus says they're giving Kirk fifteen minutes on air, but then that the centurion should kill Kirk with a single clean blow - that's not going to take 15 minutes!
During the first escape McCoy hits a guard in the chin. Despite the fact the guy's wearing a helmet with a metal chinguard, he goes down and McCoy's hand appears fine.
McCoy: (to Kirk) I read in your report that Flavius was killed. I'm sorry. I really liked that sun worshipper.
Spock: I do wish we could examine that belief of theirs more closely.
Uhura: I'm afraid you have it all wrong. All of you. I've been monitoring their old style radio broadcasts. The Empire's spokesman trying to ridicule their religion. But he couldn't. (after a brief silence) Don't you understand? It's not the sun up in the sky. It's the Son of God!
Kirk: Caesar and Christ. They have them both.
Spock: It will replace their imperial Rome, but it will happen in their twentieth century.
Kirk: And the word is spreading... only now. Wouldn't it be something to watch it happen all over again?
Policeman: Come, Flavius. You've been matched for the morning games.
Flavius: I will not fight. I'm a brother of the sun.
Policeman: Put a sword in your hand and you'll fight. I know you, Flavius. You're as peaceful as a bull.
Scotty: The landing party is in trouble, and I'm under orders not to interfere. However, no order can stop me from frightening them. May do no good, but it might suggest to someone what a starship can really do. Aye!
Claudius: I pity you, Captain Merik. But at least watch and see how men die!
Claudius: So this is a Vulcan. From what I've heard I wish I had fifty of you in the arena.
Merik: (after witnessing the landing party's escape attempt) Well done, Jim. But I'm afraid it won't be that easy. They've been handling slaves for over two thousand years.
Claudius: But it was exciting. They'd do well in the arena.
Policeman: Runaway slaves are always welcome. (pulls Spock's cap off, revealing the Vulcan ears) No not slaves. Barbarians! It's been a long time since I've watched barbarians die in the arena!
Claudius: The games have always strengthened us. Death becomes a familiar pattern. We don't fear it as you do.
Claudius: We believe men should fight their own battles. Only the weak will die.
Kirk: It is one of our most important laws that none of us may interfere with the affairs of others.
Marcus: Guards. Take (Kirk) to the arena. Oh, we've pre-empted 15 minutes on the early show for you...in full color. We guarantee you a splendid audience. Oh, you may not understand because you're centuries beyond anything as crude as television.
Kirk: I've heard it was...similar.
Marcus: Would you leave us, Merik? The thoughts of one man to another cannot possibly interest you.
Marcus: You're a Roman, Kirk, or you should have been.
McCoy: Spock, uh...I know we've had our disagreements. Maybe they're jokes. I don't know. As Jim says, we're not often sure ourselves sometimes, but what I'm trying to say is --
Spock: Doctor, I am seeking a means of escape. Will you please be brief?
McCoy: Well, what I'm trying to say is you saved my life in the arena.
Spock: Yes, that's quite true.
McCoy: I'm trying to thank you, you pointed-eared hobgoblin!
Spock: Oh, yes. You humans have that emotional need to express gratitude. 'You're welcome', I believe, is the correct response. However, Doctor, you must remember I am entirely motivated by logic. The loss of our ship's surgeon, whatever I think of his skill, would mean a reduction in the efficiency of the Enterprise...
McCoy: Do you know why you're not afraid to die, Spock? You're more afraid of living. Each day you stay alive is just one more day you might slip and let your human half peek out. That's it, isn't it? Insecurity. Why, you wouldn't know what to do with a genuine, warm, decent feeling.
Spock: Really, Doctor.
McCoy: I know. I'm worried about Jim too.
McCoy: Angry, Mr. Spock, or frustrated, perhaps?
Spock: Such emotions are foreign to me, Doctor. I'm merely testing the strength of the door.
McCoy: For the fifteenth time.
Achilles: Stop running! Fight!
Spock: Need any help, Doctor?
McCoy: Whatever gave you that idea?
Achilles: Fight, you pointed-ear freak!
McCoy: You tell him, buster. Of all the completely...ridiculous...illogical questions...I ever heard in my life!
Marcus: Admit it. You find these games frightening, revolting.
Kirk: In some parts of the galaxy, I have seen forms of entertainment that makes this look like a folk dance.
Spock: Fascinating. This atmosphere is remarkably similar to your 20th century. Moderately industrialized pollution containing substantial amounts of carbon monoxide and partially consumed hydrocarbons.
McCoy: The word was "smog."
Spock: Yes, I believe that was the term. I had no idea you were that much of a historian, Doctor.
McCoy: I am not, Mr. Spock. I was simply trying to stop you from giving us a lecture on the subject.
Master of Games: You bring this network's ratings down, Flavius, and we'll do a special on you!
Marcus: I believe you all swear you'll die before you'd violate that Directive. Am I right?
Spock: Quite correct.
McCoy: Must you always be so blasted honest?
Merik: I think you can see why they don't want to have their stability contaminated by dangerous ideas of other ways and places.
Spock: Interesting, and given a conservative empire, quite understandable.
McCoy: Are you out of your head?
Spock: I said I understood it. I find the checks and balances of this civilization quite illuminating.
McCoy: Next he'll be telling us he prefers it over Earth history.
Spock: They do seem to have escaped the carnage of your first three world wars, Doctor.
McCoy: They have slavery, gladiatorial games, despotism...
Spock: Situations quite familiar to the six million who died in your first world war, the 11 million who died in your second, the 37 million who died in your third. Shall I go on?
Marcus: Interesting. And you, Captain...which world do you prefer?
Kirk: My world, proconsul, is my vessel, my oath, my crew.
Flavius: The message of the sun, that all men are brothers, was kept from us. Perhaps I'm a fool to believe it. It does often seem that man must fight to live.
Kirk: You go on believing it, Flavius. All men are brothers.
(as Spock and Bones banter)
Flavius: Are they enemies, Captain?
Kirk: I'm not sure they're sure.
McCoy: Quite logical, I'd say, Just as it's logical that a 20th-century Rome would use television to show its gladiator contests or name a new car the Jupiter 8.
Spock: Doctor, if I were able to show emotion, your new infatuation with that term would begin to annoy me.
McCoy: What term? Logic? Medical men are trained in logic, Mr. Spock.
Spock: Really, Doctor, I had no idea they were trained. Watching you, I assumed it was trial and error.
Flavius: What do you call those?
Spock: I call them ears.
Flavius: Are you trying to be funny?
McCoy: Just once I'd like to be able to land someplace and say, "Behold, I am the Archangel Gabriel".
Spock: I fail to see the humor in that situation, Doctor.
McCoy: Naturally. You could hardly claim to be an angel with those pointed ears, but say you landed someplace with a pitchfork...
This episode marks the first and only time that the original series makes direct mention of current established religious beliefs when Uhura states that after monitoring the planet's transmissions, she realized that the inhabitants were not referring to "the sun up in the sky" but to "the son of God". Kirk then remarks "Caesar and Christ, they had them both and the word is spreading only now."
Desilu No: 5149-43.
Story writer John Kneubuhl is uncredited.