Captain's log -- star date 5121.5, orbiting the second planet in the Minarian star system. This star has long given evidence of entering a nova phase, and six months ago, a research station was established to make close-up studies of the star as its end approaches. Minara is now entering a critical period, and the Enterprise has been ordered to evacuate the station before the planet becomes uninhabitable. Yet our attempts to contact the station's personnel have been, so far, unsuccessful. Dust. Apparently these instruments have not been recently used. A record tape. Maybe it'll tell us something about the personnel that lived here. Enterprise to Captain Kirk. Come in, please. Kirk here. What is it, Enterprise? Scott here, sir. Our instruments have picked up a gigantic solar flare with very high levels of cosmic rays accompanying it. How bad? An enormous one. Our sensors indicate the cosmic ray concentration measures 3.51 on the Ritter scale. That'll play the very devil with the crew, as well as the ship. At that rate, it will take exactly 74.1 solar hours for the storm to pass. Get the ship out. Stay at minimum distance for absolute safety. Aye, aye, sir. We'll beam you up in-- Negative. We're staying here. The atmosphere will protect us. Get that ship out of here, Mr. Scott. Very well, sir. Scott out. Mr. Spock, what about that tape? Remember, Captain, what we see on this tape happened approximately three months ago. I don't think I can stand another week in this godforsaken place. "In his hand are the deep places of the earth--" Psalm 95, verse 4. Looks like he was listening. Who's out there? What happened to them? Where's does that sound coming from? Spock, can you pinpoint it? Negative, Captain. It doesn't register. Bones! Spock! Space-- the final frontier. These are the voyages of the star ship Enterprise. Its five-year mission-- to explore strange new worlds... to seek out new life and new civilizations... to boldly go where no man has gone before. Spock... Bones... Where are we? Exactly 121.32 meters beneath the planet surface, Captain. How did we get here? Residual energy readings indicate we were beamed here by a matter-energy scrambler, similar to our own transporter mechanism. That's a nasty cut. Does it hurt? No. Captain, picking up a life-form reading-- bearing 42 mark 7. One of the missing scientists? Negative. Although humanoid, it is definitely not Homo sapiens. Identification. Impossible. I can make no exact identification other than it being humanoid. Let's find out. Phasers on stun. Approaching the life-form, Captain. What is it? Still undistinguishable. Be careful. Why, she seems harmless enough. The sand-bats of Manark-4 appear to be inanimate rock crystals, Doctor... until they attack. We're not going to hurt you. Is this your home? Do you live here? What about it, Spock? Analysis. From what we know of the specific gravity and other environmental factors of this planet, a life-form such as hers could not evolve here. Are you responsible for bringing us here? Don't be afraid. Bones, what's wrong with her? She's a mute, Jim. No vocal cords, not even vestigals. And I don't think it's a pathological condition. Explain. She appears to be perfectly healthy. As for the other, her lack of vocal cords could be physiologically normal for her species, whatever that is. A race of mutes, like the civilization on Gamma-Vertis-4. That's my observation, for whatever it's worth. Without speech, how's she going to be able to understand us? Unless she's a telepath. An unlikely possibility, Captain. Since over 98% of the known telepathic species send thoughts as well as receive them. She's made no attempt to contact our minds. We can't keep referring to her as "she," as if she weren't here. You have any ideas? I don't know about you, but I'm going to call her Gem. Gem, Doctor? Well, that's better than, "Hey, you." I want to know why we're here. I want to know what's going on. And she knows. I'm Captain-- We are aware of your identity, Captain. Who are you? Why did you bring us here? We are Vians. Do not interfere. What do you intend to do with us? Delay us no longer. We come-- Since you already know who we are, you must also know that we come in peace. Our prime directive specifically prohibits us from any interference-- I...can't... seem...to stand up. Don't... fight... the force field. There's something about it that upsets the... body metabolism. Not quite, Doctor. The field draws its energy from your bodies. The more you resist, the stronger the force field becomes. Ah, sufficient. Mr. Spock... there must be an exit other than the one we just saw. Correct, Captain. You feel all right, Jim? Don't worry about me. They may have hurt her. Did they hurt you? The pain is gone. She touched my head, and the pain is gone. The wound is completely healed. It fits, Jim. She must be an empath. Her nervous system is so sensitive, highly responsive that she can actually feel our emotional and physical reactions. They become part of her. Thank you. Captain, in this direction, my tricorder is now picking up a substantial collection of objects. Details. Electronically sophisticated devices. I fail to understand why my tricorder previously gave no indication of them being there. They're there now. Let's go check them out. Staying here alone could be dangerous. Come with us. Fascinating. Look at this stuff. Bones... Spock, come here. Jim, Spock. You are on schedule. Some further simple tests are necessary. We've seen the results of some of your tests. I found our missing men... dead. Another one of your experiments? You're wrong. Their own imperfections killed them. They were not fit subjects. Come. Time is short. Yes. Your time is running out. This sun is about to nova. When it does, it'll destroy you, this planet, and this insane torture chamber. Let's get out of here. Readings indicate the passage to the surface lies in this direction. Kirk to Enterprise. Kirk to Enterprise, come in. Out of range. Readings, Mr. Spock. The research station 6 kilometres in that direction, captain. Let's get there as fast as we can. If the Enterprise has a search party, it'll be there. Spock! Much further? Just ahead. Hey, Jim, look. Scotty and a search party. Scotty! Scotty! Stay there! Come on! We're coming! Keep going. Their will to survive is great. They love life greatly to struggle so. The prime ingredient. Where did they go? I believe they were never actually present, Doctor. It was a mirage. Where's Kirk? Jim. What are you doing here? Where's Scotty? Captain, it was a mirage. Captain Kirk! We have decided that one specimen will be sufficient. You will come with us. What about the others? We've no interest in them. They may go. Very well. You can't go back there. You'll end up like the other two. Captain, I request permission-- Denied! But, Captain-- You have your orders. What happened to my men? They are safe. One specimen. You said one specimen! What happened to my men? Indeed, the prime ingredient. Where are they? Tell me! You said you'd let them go! Mr. Sulu, will you give us an estimate of how much longer we'll have until those solar flares will subside? Aye, sir. Readings now indicate 2.72 on the Ritter scale. At the present rate of decrease, we'll have to wait at least 17 hours more before we can even attempt to enter orbit. Aye. Well, as long as we're stuck out here, we might as well relax until the storm passes. The storm's already lasted four hours longer than we've anticipated. Do you suppose our landing party could be in any danger? That's not likely. The planet's atmosphere will give them ample protection. And if I know Captain Kirk, he'll be more worried about us than we are about him. What is it you want to know? We seek no information as you mean. Your civilization is yet too immature to have knowledge valuable to us. You don't need any knowledge from us, yet you're willing to kill for it. Is that what happened to Linke and Ozaba? We did not kill them. Their own fears killed them. Well, what did you expect from them? And what do you want from me? We've already observed the intensity of your passions and gauged your capacity to love others. Now we want you to reveal to us your courage and strength of will. Why? What is it you hope to prove? If my death is to have any meaning, at least tell me what I'm dying for. If you live, you will have your answer. Come on, Spock, the passageway was there before. It's got to be there. Doctor, I'm unable to lock in on the previous readings. I can find no exit out of here. Captain! Jim, what is it? What have they done to you? Help him! Don't be afraid to help him. Gem? You lie still. I'll check her out right away. Will she live? She seems fine now. Can you explain what happened? Complete empathy. She must be a totally functional empath. Her nervous system actually connected to yours to counteract the worst of your symptoms. With her strength, she virtually sustained your body's physiological reactions. But she weakened. I could feel it. Is her life in danger? It's impossible to say yet, but supplying your body with life support did drain her. Her withdrawal seemed to suggest the fear of death, Doctor. Only your urging her on caused her to continue. That's true. Fear would naturally be her first reaction. Perhaps she doesn't know our captain well enough yet to offer up her life. Could the strain really have killed her? Yes. However, I'd assume that her instinct for self-preservation would take over to prevent it. How do you feel? I'm... tired. Can you recall what happened, Captain? I remember the laboratory, and they wanted to know something. But l... I can't remember. Take it easy. What's the matter with me? You have all the symptoms of the bends. Nitrogen bubbles in your blood caused the pain. Now how would one get the bends down here? You'll have to ask the Vians. Will I live? Well, you could use some time in a decompression chamber. But otherwise, I'd say your recovery is about miraculous. I wish I could take the credit for it, but she did the work. Captain, I noted that a light preceded you at the moment you were returned here from the Vian's laboratory. Spock, why do you have to get so analytical-- No, he's right. Continue. I conclude such a light is an energy transfer point linking this device to the power source. Can you tap into it? If I could determine the frequency at which this device operates, I might be able to cause it to function for us. And get us out the same way we were brought in. I would say so. Then I'd say proceed. You are called captain. You are responsible for the lives of your crew. Is this correct? It is. We find it necessary to have the cooperation of one of your men in our efforts. We will not cooperate. When we resume our interrogations, you will decide which of your men we shall use. It is essential. There's an 87% chance that the doctor will die, and while Commander Spock's life is not in danger, the possibility is 93% that he will suffer brain damage, resulting in permanent insanity. How's it coming, Spock? I do not know, Captain. I begin to understand its operating principles, but that's all. Spock, It won't be long before the Vians come back. You better find out how that thing works and soon. Take it easy, Bones. Men weren't intended to live this far underground. It's just not natural. And space travel is? Some men spend the majority of their lives in mines beneath the surface. I'm a doctor, not a coal miner. I've recorded my principles and theories on the tricorder, Doctor. Should the Vians return, there's sufficient data for you and the captain to complete the adjustments. I'm not a mechanic. I couldn't get that thing to work no matter how many notes you left. Possibly not, but you and the captain together will be able to do so. In any case, Spock, you're the logical one to leave with the captain. The decision's mine. If there are any decisions to be made, I'll make them. If and when it becomes necessary. I don't need any. I'm still chief medical officer of the Enterprise. I'll tell you what you need and when you need it. Would you rather have the bends? That's it. Just lie down and relax. How long will he be asleep, Doctor? Between the emotional strain and that attack of bends, he's in pretty bad shape. I'm not criticizing your action, Doctor. On the contrary, I'm quite grateful for it. The captain will be spared the strain of making so difficult a decision. You have simplified the situation considerably. How? While the captain is asleep, I am in command. When the Vians return, I shall go with them. You mean, if I hadn't given him that shot-- Precisely. The choice would have been the captain's. Now it is mine. Your action is highly unethical. My decision... stands. Not this time, Spock. The choice has been made. You stay here with my friends. They'll take care of you. Do you understand? Come, then. Doctor, please understand that if there was any other way to accomplish our purpose... Get on with it. Why did you let him do it? I was convinced in the same way you were, by the good doctor's hypo. Anything? Hmm. A most unusual device. It is a control unit, but not a control mechanism. It is not a mechanical device. What exactly is it? This control is attuned to one electrical pattern of energy, the pattern produced by the mental impulses of the person who possesses it. It is activated solely by mental commands. Can you adapt it, reattune it to fit our brain pattern? I shall attempt to do so. However, it is not possible to adjust the control to fit more than one pattern at a time. I am, of course, most familiar with my own pattern. Therefore, with your permission-- Do whatever you have to to make it work, Spock. What disturbs me is why the Vians let us keep it. Fascinating. They must have known we were capable of comprehending this control and making use of it. And that we would use it to escape. The only logical assumption is that they wish to let us go. And they keep McCoy? That is evidently their intention, Captain. Somehow, you're the crux, the focal point of all this. Even before we got here, she was a prisoner. They didn't hurt her or even threaten her. Indeed, the facts would indicate that she's essential to their purpose. Yes, there is a purpose, but what is it? Has all the pain and terror happened or been made to happen... for you? Completed, Captain. The adjustments are delicate. They may not survive more than even one use. However, there should be sufficient energy to transfer us to the Enterprise. Will it take us to McCoy? If you so desire. The best defense is a strong offense, and I intend to start offending right now. Aim for the lab. Bones. Spock. Get him down. His wrists. His pulse is almost gone. How is he? Severe heart damage. Signs of congestion in both lungs. Evidence of massive circulatory collapse. Don't talk. Don't speak. Take it easy until we get you back to the ship. What is it? What's the matter? He's dying, Jim. We can make him comfortable, but that is all. You don't know. You're not a doctor. Internal injuries. Bleeding in the chest and abdomen. Hemorrhage of the spleen and liver. 70% kidney failure. He's right, Jim. Being a doctor has its drawbacks. I... always wondered why l-- Thanks. How long? It could happen anytime. The correct medical phrase, eh, Spock? You've got a...a good bedside manner, Spock. Can't we do something? I'm afraid not. Gem might be able to help him, the way she helped me, but could his nearness to death also kill her? Uncertain, Captain. Dr. McCoy's analysis of her reaction assumes that her instinct for self-preservation would prevent it. However, we cannot be positive. If she could just strengthen him and keep him from sinking further into death, we might be able to save him. No interference will be permitted. She can save his life. Let us help her to go to him. She must not be urged or forced to take action. All must proceed without interference. The purpose that brought us together-- What purpose can all this serve, except the fulfilment of some need of yours? We have but one need left in life-- to see the completion of the final moment of our test. Be patient. Patient? Our friend is dying. Perhaps. What purpose can be served by the death of our friend, except to bring you pleasure? Surely beings as advanced as yourselves know that your star system will soon be extinct. Your sun will nova. We know. Then you also know that the millions of inhabitants on its planets are doomed. That is why we are here. This arena of death that you have devised for your pleasure-- Will it prevent this catastrophe? No, it will not, but it may save Gem's planet. Of all the planets of Minara, we have the power to transport the inhabitants of only one to safety. If Gem's planet is the one that will be saved, we must make certain beyond any doubt whatsoever they are worthy of survival. How will the death of our friend serve this purpose? His death will not serve it, but her willingness to give her life for him will. You were her teachers. We were? What could she learn from us? Your will to survive. Your love of life. Your passion to know. They are recorded in her being. Her planet will be fortunate. Each of you was willing to give his life for the others. We must now find out whether that instinct has been transmitted to Gem. Time grows short. You were correct, Captain. Everything that has occurred here has been caused to happen by them. This has all been a great laboratory. We have been the subjects of the test. No. We only created the circumstances. That was necessary. Your actions were spontaneous. Everything that is truest and best in all species of beings has been revealed by you. Those are the qualities that make a civilization worthy to survive. Behold. That is most significant. An instinct new to the essence of her being is generating. Compassion for another is becoming part of her functioning life system. She is afraid. She's saving herself. She does not yet have the instinct to save her people. We have failed. No. No, not yet. Captain, Dr. McCoy's life is not solely dependent on Gem. The Vians, too, must be capable of saving his life. True. Then you cannot let him die. His death is not important. We must wait to see whether her instinct for self-sacrifice has become stronger than her instinct for self-preservation. Don't touch me. Stay away. Jim. Spock. Are you here? Yes, Bones. Don't let her touch me. She'll die. Jim... I can't destroy life, even if it's to save my own. I can't. You know that. I can't let you do it. Captain. What is it? The intensity of emotion is draining us and building up the force field. Yes, I know. It draws its energy from us, Captain. In spite of what we see, all emotion must be suppressed. That might weaken the field. I'll try. Yes. Spock. We cannot use our powers to change what is happening. You must save the life of our friend. No. We will not. Her instinct must be developed to the fullest. The test must be complete. It is complete. Gem has earned the right of survival for her planet. She offered her life. To offer is not proof enough. If death is all you understand... here are four lives for you. We will not leave our friend. You've lost the capacity to feel the emotions you brought Gem here to experience. You don't understand what it is to live. Love and compassion are dead in you. You're nothing but intellect. Farewell. Strange. What is puzzling you, Captain? I'm not puzzled, Mr. Spock. I am... awed. I'm with you, Captain. She awed me. No, no. I wasn't thinking of Gem. I was thinking of that fantastic element of chance that out in limitless space we should come together with Gem. Captain, the element of chance can virtually be eliminated by a civilization as advanced as the Vians. Not to dispute your computer, Mr. Spock, but from little what you've told me, I'd say she was a pearl of great price. What, Scott? You don't know the story of the merchant? The merchant... who, when he found one pearl of great price, went and sold all that he had and bought it. Yes, she was all that. And whether the Vians bought her or found her makes little difference-- she was of great value. Well, personally, I find it fascinating that with all their scientific knowledge and advances, that it was good old-fashioned human emotion that they valued the most. Perhaps the Vulcans should hear about this. Mr. Spock, can you be prevailed upon to bring them the news? Possibly, Captain. I shall certainly give the thought all the consideration it is due. Mr. Sulu, ahead warp factor 2. Aye, aye, sir. Warp factor 2.