[Bridge]

SULU: We will intercept the cloud in the vicinity of Alondra, the outermost planet, sir.
SPOCK: Captain, we are now approaching sensor range of the cloud.
KIRK: Readings?
SPOCK: It seems to be of irregular shape, some eight hundred thousand kilometres across and about half that in depth.
AREX: It's immense. Twice the diameters of Saturn, Jupiter and Neptune together!
KIRK: Put up our present position, Lieutenant Arex.
AREX: Yes, Captain.
KIRK: Reading, Spock?
SPOCK: This is very curious, Captain. It computes as a strange combination of matter and energy.
SULU: Captain, look.
AREX: Captain, Alondra has disappeared from navigation scan.
UHURA: The cloud could have come between us and the planet.
SPOCK: No, Lieutenant, the cloud has engulfed Alondra. Captain, the planet seems to be breaking up. Its mass is definitely growing smaller.
KIRK: Spock, is it possible the cloud consumes planets?
SPOCK: It seems a logical assumption, Captain.
SULU: Sir, the cloud is changing course.
KIRK: That's impossible.
AREX: The course change is verified, sir. The cloud is now moving directly toward the inhabited planet.
UHURA: But if it continues on that course
KIRK: Mantilles will die. Mister Sulu, increase speed to warp eight. Push it to the limit.
SULU: Yes, sir.

Captain's log, supplemental. At warp eight, we will intercept the cloud before it reaches the inhabited planet Mantilles. But we are uncertain what we can do to stop a matter-energy cloud which measures thousands of times more than our vessel.

[Bridge]

MCCOY: Jim, if we can't stop it, millions of people will die.
SPOCK: Perhaps more, Doctor. If planet annihilation is part of this thing's nature, it might seek them out as instinctively as an amoeba seeks out food. It may not consume only planets, but also stars. We do not know yet whether it has any selective ability, but it could be a thread to every planet in our galaxy.
KIRK: Bones, I need an expert psychological opinion. Do we dare tell the people on Mantilles, try to save a few who could get away?
MCCOY: How much time do they have?
AREX: Four hours, ten minutes, sir.
MCCOY: It's certain there'd be planetwide panic.
KIRK: Blind panic.
SPOCK: On the other hand, notifying them may still save some small fraction of the population, Captain.
MCCOY: Who's the governor of Mantilles, Jim?
KIRK: Bob Wesley. He left Starfleet for the governorship. He's no hysteric.
MCCOY: Then tell him.
SULU: Coming up on the cloud, sir. ETA five minutes, ten seconds.
KIRK: Thanks, Bones. Lieutenant Uhura, send a priority one call to Governor Wesley on Mantilles.
UHURA: Aye, aye, sir.
SPOCK: Captain, I'm getting unusual readings on the chemical identity sensors.
KIRK: What kind?
SPOCK: Elements unknown in our periodic tables, Captain. I'm of the opinion this cloud has come from outside our galaxy.
SULU: Captain.
KIRK: Evasive action.
AREX: Aye, sir.
(But the cloud wraps tendrils around the Enterprise)
KIRK: Reverse full power.
SULU: Full reverse, sir.
MCCOY: It's still got us.
SPOCK: The streamers are a combination of koinoenergy, almost an ambiplasma with an unusually powerful attraction force.
KIRK: Prepare to fire all phasers into cloud mass.
SULU: Locked on. Phasers ready, sir.
KIRK: Fire.
SULU: Firing. No effect, Captain
SPOCK: The cloud appeared to absorb the phaser energy, Captain.
(The ship is shaken)
MCCOY: We're floating inside the cloud.
UHURA: All decks report considerable shaking up, but no damage, sir.
SULU: Captain, objects approaching on the bow.
KIRK: Deflector shields on.
AREX: Shields up and operating, sir.
SULU: More objects approaching aft, sir.
KIRK: Analysis, Spock?
SPOCK: The objects are some form of highly charged gaseous antimatter.
SCOTT [OC]: Engineering to Captain Kirk.
KIRK: Kirk here.

[Engineering]

SCOTT: Captain, the power drain on the shields is too heavy to hold for any length of time.
KIRK [OC]: I know, Scotty.

[Bridge]

KIRK: Scotty, prepare the shields for an antimatter charge.
SCOTT [OC]: Aye, sir. Engineering out.
SULU: Antimatter charge ready, sir.
KIRK: Fire.
(More blobs approach the ship)
KIRK: Double the charge.
SULU: Ready, sir.
KIRK: Fire.
(The blobs disappear)
KIRK: Well, Spock, any conclusions?
SPOCK: Only the beginning of a theory, Captain. It is possible this cloud in which we are entrapped is a living thing. The cloud is alive. Yes, Captain, its components appear similar to those found in living organisms.
KIRK: Bones, any opinion?
MCCOY: There's some resemblance. I don't know how much we can depend on it. But I'll tell you one thing. We have to get out of this area. Those mists out there are acting something like a macromorphase enzyme. If the shields don't stay up, the hull will be corroded and we'll all be broken down into nice digestible particles.
SPOCK: I am inclined to agree with the Doctor, Captain. The mass of the planet Alondra has been steadily growing smaller since we've been in here.
UHURA: Captain, I have a subspace radio message coming in from Governor Wesley of Mantilles.
KIRK: Transfer it to my quarters.
UHURA: Yes, sir.
KIRK: Mister Sulu, use your scanners to assemble a diagram of the cloud's composition and feed it to the library computer.

[Kirk's quarters]

WESLEY [on monitor]: Three and a half hours, Jim. That's not enough. Even if I had the ships available to totally evacuate the planet.
KIRK: You have time to save some people, Bob.
WESLEY [on monitor]: That won't be long enough either, but it'll have to do.
KIRK: How are you going to choose?
WESLEY [on monitor]: There is no choice, Jim. We'll save the children.

[Bridge]

KIRK: In three hours and twenty minutes the cloud will reach Mantilles. Millions of people will die. I need your help, gentlemen. Your analyses?
SPOCK: If we assume the cloud is a living being, we must also assume it needs some kind of food to sustain itself.
KIRK: Agreed. Judging from the disappearance of Alondra, the cloud lives on the energy it converts from the planets it consumes.
SPOCK: Exactly. It is like a huge bull grazing here and there in the pasture of the universe.
KIRK: What about those blobs, Bones?
MCCOY: I think they perform the same function as teeth. They break up the larger chunks of matter for digestion.
KIRK: Lieutenant, let's see what the scanners have come up with on the cloud's composition.
(A vaguely familiar shaped object with bilateral symmetry and a central dense core. The subtly makes my brain hurt.)
KIRK: It seems to have some sort of anatomy. Arex, where are we on that chart?
AREX: Posting Enterprise position, sir.
KIRK: The opening where we were drawn in seems to have closed. But there's another opening up there on top.
MCCOY: If this thing does have some kind of digestive system, we don't stand much of a chance of making it that far.
AREX: Three hours, five minutes until the cloud reaches Mantilles, sir.
KIRK: Thank you, Mister Arex. Since we appear to have only one way out, we're going to take it. Mister Sulu, takes us to that central core area.
SULU: Aye, aye, sir.
KIRK: And if this thing does have a stomach, we just might be able to give it enough indigestion to make it turn away from Mantilles.
(Later)
SULU: We've reached the entrance to the central core, Captain.
MCCOY: What do we do now, knock?
(Enterprise shakes)
KIRK: No need, Bones. Here we go.
(The Enterprise is sucked in to an area with bits protruding from walls, and the blobs following get blown up)
UHURA: What are those things?
MCCOY: I think we're in what corresponds to the small intestine. Those things growing out of the wall would be similar to villi.
KIRK: Villi?
MCCOY: The human small intestine is lined with millions of them, to absorb nutrients into the body.
(Another explosion)
SPOCK: Captain, those villi are antimatter. It the Enterprise touches one of them
KIRK: We'll explode. Mister Sulu, keep the deflectors up at all costs.
SULU: Yes, sir.
KIRK: Incredible. They're destroyed on contact with the matter this thing takes in and then they regenerate immediately.
SCOTT [OC]: Scott to Bridge.
KIRK: Yes, Scotty.
SCOTT [OC]: Keeping the deflectors this high

[Engineering]

SCOTT: Is putting an enormous strain on the engines, Captain. Especially the antimatter. What with the maximum power demands and all, the reserve is falling fast.

[Bridge]

KIRK: How much time do we have?
SCOTT [OC]: Twenty one minutes, sir.

[Engineering]

SCOTT: But if the indicator goes below two anti-kilos, the engines won't regenerate.

[Bridge]

KIRK: Thank you, Mister Scott. Mister Arex, try to make your way through to the opening on the other side.
AREX: Yes, sir.
(Enterprise glides serenely along the jagged canyon)
SULU: I can't hold it on course, sir. We're using all power.
KIRK: Increase deflector shields to maximum.
AREX: Screens to maximum, sir.
(The ship slows, and seems to drift in a current)

Captain's log, supplemental. The Enterprise has only fifteen minutes left before her power is drained and we are left helpless.

[Engineering]

SCOTT: If we don't stop the power drain right now, that'll be the end of us.
KIRK: And if we do stop, we'll be drawn into one of the villi and the ship will explode.
SCOTT: Captain, you said that villi are antimatter. If we could get a piece of it, I could put it in the antimatter engine and it would regenerate. We'd have enough power for the engines and the shields to go on maximum again.
KIRK: We need both the matter and the antimatter engines regenerated.
SCOTT: Matter's no problem. We could beam aboard some of the planet chunks out there. And we can cut a piece of the antimatter villi with the tractor beams and transport it aboard like that.
KIRK: Bring it aboard? If the antimatter touches the inside of the ship or any of us, we'll be blown to bits.
SCOTT: I can rig a force field box that'll hold the villi suspended in the centre. Then I can take it into the antimatter nacelle, put it into the regenerating chamber and release the forcefield by remote control.

[Transporter room]

(So a piece of villi is cut and Kyle transports it into Scott's box)
KIRK: Scotty, we've got ten minutes left.
SCOTT: The force field is holding. Let's go.

[Antimatter nacelle]

(Things are spluttering due to lack of fuel)
SCOTT: Well, that gives us two minutes. All right, Gabler, open it. (They push the box in) Close it.
(The spluttering stops)
KIRK: Scotty, you've just given the Enterprise and Mantilles a chance to live.
SCOTT: Thank you, sir.

[Bridge]

KIRK: Situation, Mister Spock?
SPOCK: The cloud is now only forty two minutes, fourteen seconds from Mantilles, Captain. And we have ascertained an important fact. This being does have a brain.
KIRK: Intelligent?
SPOCK: Impossible to say at this moment, Captain. It has made only one action which might be interpreted as intelligent. It changed course from Alondra toward Mantilles. But that could have been an involuntary response to the sensing of food.
KIRK: Where is the brain located?
SPOCK: That irregularly shaped object at the top of the core emanates considerable electrical activity.
MCCOY: It's pretty certain to be the brain, Jim. The functioning of the brain is basically electric.
KIRK: If we can reach it before the cloud gets to Mantilles, we might be able to save the planet. We'll use the photon torpedoes to destroy the brain.
SPOCK: Captain, this is a living creature. Starfleet regulations
KIRK: I know the regulations against the killing of intelligent life forms, Mister Spock. But we don't know this life form is intelligent. And we do know the people on Mantilles are doomed if we don't stop it. If I have to be a judge, I decide in favour of saving Mantilles.

Captain's log, stardate 5372.0. Spock and Uhura are using our sensors to prepare a detailed chart so we may determine targets for our photon torpedoes.

[Bridge]

KIRK: Am I doing the right thing, Bones? Once, I said, man rose above primitiveness by vowing 'I will not kill today.'
MCCOY: But you can't let this thing destroy over eighty million lives, either.
SPOCK: Captain, I have completed the analysis of the target area. Unfortunately, the brain is so vast, our entire offensive armament will not assure its destruction. However, the brain could be completely destroyed if we convert the entire ship to energy, aimed at the brain's cortex, and expend the energy in one mortal strike.
MCCOY: That sounds like you're telling us to blow up the ship.
SPOCK: I believe that is what I just said, Doctor.
KIRK: Your figures are specific and absolutely correct, of course? You're sure it will do the job?
SPOCK: Yes, Captain. Quite sure.
KIRK: Kirk to Engineering.
SCOTT [OC]: Engineering. Scott here.

[Engineering]

KIRK [OC]: Mister Scott, prepare the self-destruct mechanism in the Engineering core.

[Bridge]

KIRK: Computer control will be on the Bridge when it's time to trigger it.
SCOTT [OC]: Aye, sir.
UHURA: Incoming message, sir. It's Governor Wesley of Mantilles.
KIRK: Put it on the viewscreen, Lieutenant.
UHURA: Yes, sir. Go ahead, Governor.
WESLEY [on viewscreen]: Jim.
KIRK: Bob. Is the evacuation proceeding?
WESLEY [on viewscreen]: As best it can. There was some hysteria at the beginning, but most agreed to let the children be taken off first. But it's only five thousand children out of eighty two million people.
KIRK: I know.
WESLEY [on viewscreen]: We can see the cloud approaching, Jim.
SULU: Thirty one minutes and four seconds to Mantilles, sir.
KIRK: Bob, where's Katie?
WESLEY [on viewscreen]: Here, with me.
KIRK: Don't worry, Bon. She'll be all right. Goodbye.
WESLEY [on viewscreen]: Goodbye, Jim.
MCCOY: Who's Katie?
KIRK: His daughter. She's eleven. Spock, is there any way we could establish whether or not it is definitely intelligent? Perhaps a Vulcan mind touch.
SPOCK: It would require physical contact, which is impossible, Captain. But I may be able to reach out with my mind. If we focus our sensors onto the cloud's synaptic electrical impulses, the input could be routed to the ship's computer for analysis into thought.
UHURA: I can link in the universal translator and put it on the audio system from here.
KIRK: Can you do it in time?
SPOCK: It is impossible to calculate, Captain. There are too many unknown factors. I can only try to accomplish the link. No more.
SULU: Twenty six minutes exactly to Mantilles, sir.
KIRK: All right, Spock. Get at it.

Captain's log, stardate 5372.1. The cloud will reach Mantilles in seven minutes. Spock has been working on the mechanics of reaching the cloud's thoughts, but I doubt if there's any time left. And even if we do establish contact, can we communicate with it and persuade it not to kill?

[Bridge]

SCOTT: The procedure is ready, sir.
KIRK: Thank you, Scotty.
SPOCK: Ready, Captain. [OC] Listen to me. Listen to me. You are not alone here, there is someone else. Listen to me.
CLOUD [OC]: What?
SPOCK [OC]: You are not alone here, there is someone else. Listen to me. Listen to me.
CLOUD [OC]: What you?
SPOCK [OC]: I am another being.
CLOUD [OC]: Being? Where?
SPOCK [OC]: I am inside you.
CLOUD [OC]: Inside? Explain. Within me?
SPOCK [OC]: I am very small. And there are many of me. We are in a spaceship within you.
CLOUD [OC]: Explain.
SPOCK [OC]: A small thing which holds us all.
CLOUD [OC]: Within me?
SPOCK [OC]: Within you.
CLOUD [OC]: Explain.
SPOCK [OC]: We came to think to you. You consumed us. You thought we were food.
CLOUD [OC]: Why? Why you think to me?
SPOCK [OC]: Many of us live on the things you consume.
CLOUD [OC]: Things I consume?
SPOCK [OC]: Yes. Many of us are on the thing near you now. Do not consume it.
CLOUD [OC]: Explain.
SPOCK [OC]: The spherical thing ahead of you, the matter you intend to consume, sense it closely.
KIRK: How near is Mantilles, Mister Arex?
AREX: The cloud will envelope it in three minutes, twenty seconds, sir.
CLOUD [OC]: Perceive many somethings. So small.
SPOCK [OC]: They are beings. Alive, like you. They will all die if you consume that thing.
CLOUD [OC]: Too small.
SPOCK [OC]: Explain.
CLOUD [OC]: I am small. Some things I perceive too small. Not alive beings.
SPOCK [OC]: Listen to me. I'm going to come into your thoughts. And at the same time, you will come into mine.
CLOUD [OC]: Necessary?
SPOCK [OC]: Yes. Very.
CLOUD [OC]: Proceed.
(Spock stands up and looks around)
KIRK: Bones, he's the cloud. Its thoughts are here. Don't move. Lieutenant, use the library computer. Put some views of the Earth onto that screen.
UHURA: Yes, sir.
KIRK: This is the thing we come from. Lieutenant, this is what I want.
(Images of the ground from above, cities, children playing, countryside. And the clock ticks down to 1)
SCOTT: Awaiting your order, Captain.
KIRK: A few seconds, Scotty. We have to give Spock that much.
(Spock sits down again as the clock goes to zero)
MCCOY: Jim, if we don't self-destruct now all those people will die.
SULU: The cloud has stopped, sir.
CLOUD [OC]: Comprehend. Not desire to consume other beings.
KIRK: Quiet.
SPOCK [OC]: There are many things in our galaxy like the one you just perceived.
CLOUD [OC]: Truth?
SPOCK [OC]: Truth. You do not desire to consume other beings. It would be best if you return to your origin. The way you came. Will you do this?
CLOUD [OC]: A long journey.
SPOCK [OC]: Will you return?
CLOUD [OC]: Will return to origin place.
KIRK: Lieutenant Uhura, contact Governor Wesley. Tell him to bring his ships back.
UHURA: Yes, Captain.
KIRK: Spock, you did it! The cloud is leaving.
SPOCK: I believe so, Captain. There is a grid at the top of the brain core. It uses it to sense. We can escape the cloud through it.
KIRK: Mister Sulu, let's get out of here, through that grid.
SULU: Yes, sir!
KIRK: Spock, what did you perceive?
SPOCK: The wonders of the universe, Captain. Incredible, completely incredible.