[Bridge]

KIRK: Status, Mister Spock?
SPOCK: All systems affirmative, Captain. The Enterprise is on course and on schedule.
KIRK: It'll be nice to play diplomat for a change, eh, Spock?
(Spock grimaces in pain and falls to the floor, unconscious.
KIRK: Kirk to Sickbay. Emergency!

[Sickbay]

MCCOY: Jim, choriocytosis is a strange disease. In races with iron-based blood, it's practically nothing, but in others
KIRK: Get to the point, Bones.
MCCOY: Spock has contracted the disease. It's fatal to Vulcans.
KIRK: Are you sure?
MCCOY: I've triple-checked, Jim. I wish to God I was wrong. Spock's blood is copper-based. The infection enters the blood stream, and encases the cells so they can't carry oxygen.
KIRK: The result is suffocation.
MCCOY: Yes, Jim.
KIRK: Is there any cure?
MCCOY: One. A naturally occurring drug called strobolin. But it's only found on a few planets in the galaxy.
KIRK: Library computer.
COMPUTER: Working.
KIRK: What is the nearest strobolin supply planet to our present position?
COMPUTER: Beta Canopus. Four solar days away at maximum warp.
KIRK: How long can Spock last without the drug?
MCCOY: I can give him injections of a synthesised drug that would slow the disease. But after two days the body builds up an immunity. It loses its effectiveness. By the end of the third day, the disease will be irreversible.
KIRK: It'll take four days to get the drug, but Spock will die in three. There's got to be a way.
MCCOY: What about a rendezvous?
KIRK: Of course. If we cant go out of our way to get the drug in time, there must be another ship closer to Beta Canopus. Kirk to Bridge. Get me Starfleet, Lieutenant.

Captain's log, supplemental. We've arranged to get the strobolin needed to save Mister Spock's life. The starship Potemkin has already picked up the drug and will transfer it to a freighter, the SS Huron, for delivery to the Enterprise.

[Briefing room]

KIRK: What will the symptoms be, Bones?
MCCOY: Increasing tiredness, steadily decreasing efficiency, all the symptoms of working in an oxygen-deficient atmosphere. Kind of like the test you had to pass back at the Academy.
(A knock at the door)
KIRK: Come.
SPOCK: You wished to see me, sir?
KIRK: Yes, Spock. Sit down. We've arranged a rendezvous to pick up the drug you need.
SPOCK: I trust it will not affect our scheduled arrival at Deneb Five.
KIRK: No, it won't.
SPOCK: Will that be all, Captain?
KIRK: One other thing. I've cut your duty time in half.
SPOCK: Captain, that won't be necessary. I'm quite able
MCCOY: No arguments, Spock. Doctor's orders.
SPOCK: Anything else, sir?
KIRK: That's all, Spock. Dismissed.
(Spock leaves)
KIRK: It'll hurt seeing him like that.
MCCOY: I know. As much as it might seem at times that I can't stand that pointy-eared encyclopaedia, I don't want to see that happen to him.

[Huron Bridge]

(The crew are in starfleet uniforms)
NUMBER ONE: (its a woman) ETA at rendezvous point, two hours and seven minutes, Captain.
O'SHEA: Good. That's a pretty important drug we've got for the Enterprise. I'd just as soon get rid of it and get back to shipping just dilithium.
HELMSMAN: Sir, our sensors are picking up a ship ahead.
O'SHEA: Could the Enterprise be that early?
HELMSMAN: I'm not sure it's the Enterprise, sir. It's too far away to tell.
O'SHEA: Where's it headed?
HELMSMAN: Toward us, sir.
O'SHEA: Keep an eye on it, Lieutenant.

[Bridge]

KIRK: Time to rendezvous, Mister Arex?
AREX: One hour forty three minutes, sir.
KIRK: I hate to ask, but
SCOTT: Aye, Captain. We'll squeeze a wee bit more speed out of her.
MCCOY [OC]: McCoy to Bridge.
KIRK: What is it, Bones?
MCCOY [OC]: Tell Spock it's time for another shot.
KIRK: Mister Spock. Spock.
SPOCK: I was conserving energy, Captain.
KIRK: McCoy wants you in Sickbay.

[Huron Bridge]

HELMSMAN: Sensor readout, Captain. It's not the Enterprise closing on us, sir.
O'SHEA: Another starship?
HELMSMAN: No, sir. It's an alien ship, a design I've never seen before.
O'SHEA: Put it on the screen.
(A wicked-looking bat-like design in red appears)
O'SHEA: You're sure it's following us?
NUMBER ONE: It's on an intercept course now, Captain. And at this speed, they'll get us before we get to the Enterprise.

[Sickbay]

MCCOY: This won't hurt a bit, Spock.
SPOCK: An unnecessary assurance, Doctor, in addition to being untrue.
MCCOY: That's the last time I waste my bedside manner on a Vulcan.
SPOCK: Such restraint would be welcome.
MCCOY: Not so fast, Spock. Lie there quietly.
(The monitor buzzes then goes quiet)
MCCOY: Well, that's not too bad. Back to work, Mister Spock.
SPOCK: Thank you, Doctor.
(Spock leaves)
CHAPEL: The drug isn't working any more.
MCCOY: I know, Christine. I know. Don't worry, we'll have the strobolin soon.

[Huron Bridge]

HELMSMAN: They've increased speed, sir, closing fast.
O'SHEA: Open hailing frequencies again.
NUMBER ONE: Open, sir.
O'SHEA: To unidentified alien vessel. This is Captain O'Shea of the SS Huron. Please state your registry and purpose. Repeat. Please identify yourself and your purpose.
NUMBER ONE: It's no use, sir. They're receiving but they're not answering.
O'SHEA: Well, we've got a hold full of dilithium and that drug to protect. Evasive manoeuvres.
(But the alien stays with them)
HELMSMAN: No good, Captain. Send out an emergency signal to the Enterprise.
NUMBER ONE: Yes, sir. Message from the alien, sir.
O'SHEA: Let's hear it.
ORION [OC]: Prepare to surrender your cargo or be destroyed.

[Bridge]

UHURA: Captain, I'm getting a signal from the Huron. It's an emergency beacon, automated.
KIRK: Try ship to ship.
UHURA: I did, sir. No response.
KIRK: Sensor report, Mister Spock. Are they at the rendezvous point?
SPOCK: No, sir. They hadn't reached it.
KIRK: Compute new course, Mister Arex. Let's see what's going on.
(They arrive at the Huron)
SPOCK: The Huron's power levels are at bare minimum for life support, Captain. I'm picking up metallic debris.
KIRK: Was the Huron attacked?
SPOCK: Based on present data, I would say yes.
KIRK: Spock, are you all right?
SPOCK: Captain, I (collapses)
UHURA: Bridge to Sickbay. Emergency.

[Sickbay]

MCCOY: We've got to have that drug, Jim. The synthetic is useless now.
KIRK: Do what you can, Bones.
MCCOY: Blasted Vulcan. Why couldn't you have red blood like any normal human?

[Bridge]

KIRK: Status?
AREX: (at Spock's station) The Huron's engines are dead. Emergency battery power is operating life support systems at a low but acceptable level.
UHURA: Still unable to make contact, sir.
KIRK: Is anyone on that ship alive?
AREX: Yes, sir.
KIRK: Mister Scott, Lieutenant Uhura, come with me. Mister Sulu, you have the conn. We're beaming over.

[Huron Bridge]

(The officers are slumped over their consoles)
KIRK: Scotty, check the cargo hold. See if the drug is there.
SCOTT: Aye, sir. (leaves)
KIRK: Uhura, see if you can get a playback of the log. I want to know what happened here. Nurse, attend to the wounded.

[Huron Cargo hold]

(It's many stories high - and empty)
SCOTT: Scott to Captain Kirk.

[Huron Bridge]

KIRK: Kirk here. Report, Mister Scott.
SCOTT [OC]: There's nothing down here, Captain.
KIRK: No drug?

[Huron Cargo hold]

SCOTT: No drug and no dilithium shipment. The hold is completely empty.

[Huron Bridge]

KIRK: All right. Report back up here.
UHURA: This screen is out, sir. But we can take the tapes and play them back on the Enterprise.
KIRK: Good. Nurse, how is he?
CHAPEL: He needs surgery, Captain, but he'll live.
KIRK: Kirk to Enterprise. Ready to beam over. Have the medical team standing by.

[Sickbay]

(The beds are full now)
KIRK: How's O'Shea, Bones?
MCCOY: He'll pull through. Jim, what about Spock? If we don't have that drug in twenty hours, he'll die.

Captain's log, stardate 6335.6. The Huron has been left as space junk, its engines sabotaged. Captain O'Shea has no idea who attacked his ship, but the intruder must be found and the precious cargo retrieved.

[Bridge]

AREX: I've run the Huron's sensor tapes through the computer, sir. The intruder ship is a new design, never before encountered by Federation shipping.
KIRK: Can we track it?
AREX: Yes, sir. The intruder ship produces a unique trail of radioactive waste, now bearing two one two degrees mark one seven five.
KIRK: Lay in that course, Sulu. Ahead warp factor seven.

[McCoy's office]

KIRK: How is he, Bones?
MCCOY: Not good, Jim. I'll have to put a respirator on him to help him breathe soon.
KIRK: We're following the intruder ship's trail.
MCCOY: We don't even know it it's the right one.
KIRK: It's got to be.
MCCOY: What's the use of being a doctor, anyway? We're only as good as our drugs and technology make us. Underneath all the tricks, I might as well be practising in the Middle Ages.
KIRK: If you really believed that, Bones, you wouldn't still be a doctor after twenty five years.

[Bridge]

KIRK: Report.
SULU: Radioactive residue still bearing two one two degrees mark one seven five.
KIRK: Increase speed to warp eight.
SULU: The trail goes through the asteroid belt, Captain.
KIRK: A good place for an intruder to hide, wouldn't you say, Mister Sulu?
SULU: Perfect. And a long range sensor can show that the radioactive residue stops in the middle of the belt.
KIRK: Deflectors up. Yellow Alert. Cut speed to warp one.
(There's an explosion outside)
KIRK: What was that?
AREX: These asteroids are composed of a highly unstable mineral combination, sir. They explode upon impact with each other.
KIRK: Or anything else. Keep those deflectors up, Mister Scott.
SCOTT: Captain, if the power of those rocks could be harnessed, they'd make a fantastic source of energy.
KIRK: Also make quite a weapon. Steady as she goes, Sulu.
(Sailing through the asteroids, a beam hits the shields)
SCOTT: Deflectors holding, sir.
KIRK: Hard to port, Sulu. Let's face them head on.
(The red bat-ship comes on the viewscreen)
KIRK: Hold position. Analysis, Mister Sulu?
SULU: Standard phasers, sir. Weak, though. A diffused, low quality beam. Our deflectors can stop them.
AREX: I recognise the ship's markings, Captain. It's an Orion.
KIRK: Orion.
UHURA: They're hailing us, Captain.
KIRK: Put it on visual, Lieutenant.
(These Orions are blue-skinned, wearing green suits and half-helmets)
ORION [on viewscreen]: Enterprise, we demand that you cease your pursuit immediately. I must protest, as a representative of a neutral planet.
KIRK: This is Captain Kirk. For a neutral, you were pretty quick to fire your phasers.
ORION [on viewscreen]: We couldn't be sure you were non-hostile.
KIRK: Orion's neutrality has been in dispute ever since the affair regarding the Coridan planets and the Babel Conference of stardate 3850.3. Yesterday, a Federation freighter was attacked in this quadrant, its cargo hijacked. As the first alien ship encountered, we require you to submit to search, as per Babel Resolution A12. Reply.
ORION [on viewscreen]: We have no Federation cargo aboard. Orions are not thieves. If you don't cease this harassment, we will lodge a formal protest with your government.
KIRK: Hold on that, Uhura. Tell them to stand by.
SULU: Sensors picking up the dilithium in their hold, sir.
KIRK: What about the drug?
SULU: If they have it, it's too small an amount to detect.
KIRK: Uhura, open the channel.
UHURA: Channel open, sir.
KIRK: Enterprise to Orion vessel. I have a proposal to make. If you do have the Huron's cargo, there were some perishable drugs in it that we desperately need.

[Orion Bridge]

ORION: What would these drugs be worth to you if we had them?
KIRK [on viewscreen]: You keep the dilithium shipment, no mention of the whole incident to Starfleet or in my log, plus and additional galactic standard weight container of dilithium as payment for the drug.
ORION: We get what we want, plus our neutrality remains intact? We will consider your offer.
KIRK [on viewscreen]: Very well. Kirk out.

[Bridge]

KIRK: Kirk to Sickbay.
MCCOY [OC]: McCoy here.
KIRK: Bones, how much time?
MCCOY [OC]: Less than an hour, Jim. His body functions are slipping fast now.
KIRK: Just hold out a little longer.
UHURA: The Orions are hailing us, sir.
KIRK: Put it on the screen, Lieutenant.
ORION [on viewscreen]: Your proposal requires us to trust you. It's obvious we can't.
KIRK: Do you have a counterproposal?
ORION [on viewscreen]: Yes. A face to face exchange between you and me.
KIRK: Face to face? Where?

[Orion Bridge]

ORION: On the large asteroid near our ships. We could beam down simultaneously, and I would hand you the drug myself. You wouldn't even have to give us the extra dilithium crystals. Now it's your turn to consider.

[Briefing room]

MCCOY: It's got to be a trap, Jim.
SCOTT: No doubt of it, sir.
KIRK: It could be a trap, but it's the only way to get the drug. And Spock will die if we don't.
MCCOY: You've already made up your mind, haven't you, Jim.
KIRK: Yes, but not without precautions. I'll keep my communicator channel open so you can hear what goes on. Keep the transporter locked on me, and if anything goes wrong, Scotty, I'm trusting you.
MCCOY: If this doesn't work, we could lose you and Spock.
KIRK: If we don't try, Spock doesn't have a chance.

[Orion Bridge]

ORION: Status, Lieutenant?
LIEUTENANT: We can't outshoot the Enterprise and we can't outrun it, sir.
ORION: You're saying we can't escape?
LIEUTENANT: No, sir, we can't.
ORION: Orion's official neutrality comes before this ship or its crew. We can't take Kirk's word that he won't report this incident to Starfleet.
LIEUTENANT: The only way to do that is to destroy the Enterprise, and the only way to do that is to destroy ourselves, too.
ORION: Do you have a plan, Lieutenant?
LIEUTENANT: Yes, sir. These asteroids are made of highly explosive minerals.
ORION: Can we convert the asteroid we're orbiting into a doomsday bomb that will destroy both ships?
LIEUTENANT: Yes, sir, but
ORION: But what?
LIEUTENANT: Analysis of the asteroid shows that it can't be detonated by our phasers.
ORION: What will it take?
LIEUTENANT: A powerful explosive right on the asteroid's surface. I could rig a remote control device.
ORION: No. I'll take it with me when I beam down to meet Captain Kirk. I want the satisfaction of seeing his face when I tell him he and his crew are going to die with us. And I'm sure they don't trust us. If Kirk and I are on the asteroid, the Enterprise will stay close by.
LIEUTENANT: Very well, sir. I'll get to work.

[Bridge]

KIRK: Enterprise to Orion vessel.
ORION [OC]: What is your answer, Captain?
KIRK: I accept your terms.
ORION [OC]: Very well. We will synchronise co-ordinates and beam down in fifteen minutes.
MCCOY: Jim, we don't have a lot of time. Spock
ORION [on viewscreen]: Fifteen minutes or not at all, Captain.
KIRK: All right. Kirk out.

[Asteroid surface]

(The two Captains beam down with full life support fields on)
ORION: The drug, as promised, Captain. Scan it if you wish.

[Bridge]

KIRK [OC]: Pure strobolin. I'll take that now and we can both beam up.

[Asteroid surface]

ORION: No, Captain. I can't trust that you won't report this incident to Starfleet. If you do, my planet will lose its neutrality and be subject to Federation retaliation.
KIRK: You can't escape the Enterprise.
ORION: But we can destroy it.

[Bridge]

AREX: Picking up unusual sensor readings, Mister Scott.
SCOTT: What is it?
AREX: There's dilithium down there with them, sir.

[Asteroid surface]

ORION: I have an explosive device in my backpack that will start a molecular chain reaction and detonate this asteroid. Your ship will be destroyed.
KIRK: But so will yours.
ORION: All unsuccessful Orion missions end in suicide.
(Kirk grapples with him, to stop him pressing the button on his belt)

[Bridge]

SCOTT: The dilithium. Transporter room, pinpoint those crystals down there and beam them up!

[Transporter room]

CHIEF: Pinpointed, Mister Scott.
SCOTT [OC]: Beam them up now, lad.

[Asteroid surface]

(The Orion finally breaks free of Kirk and presses the button. Nothing happens)
KIRK: Scotty, energise.
(Kirk grabs the Orion again and they are beamed up)

[Transporter room]

(Scott and two security guards are there)
SCOTT: Captain, it was close.
KIRK: Let's get up to the Bridge.

[Orion Bridge]

ENSIGN: They're gone, sir.
LIEUTENANT: Gone?
ENSIGN: I was scanning as you ordered, and they just disappeared off the asteroid. Both the Earther and the Captain.
LIEUTENANT: He's been captured, no doubt. Arm our self-destruct system, Ensign.

[Bridge]

KIRK: Open hailing frequencies, Uhura.
(The Orion goes to put a capsule in his mouth)
KIRK: Grab him! Poison. I'm sure your ship is ready to self-destruct, Captain, but if it does, your crew will die for nothing. We're not going to let you commit suicide. Whether they die or not, you'll still stand trial, and Orion's little game of neutrality and piracy is over.
UHURA: I have the Orion vessel, sir.
KIRK: This is Captain Kirk. We have your captain as prisoner. Your choice, sir.
ORION: Disarm the self-destruct system. Prepare to surrender to the Enterprise.

Captain's log, stardate 6336.2. The Orion crew is in our brig, their ship in tow, and the Enterprise is back on course for Deneb Five.

[Sickbay]

MCCOY: Spock, there's no way you can deny it.
SPOCK: Doctor McCoy, I
MCCOY: I've waited a long time for this, and you're not going to cheat me.
KIRK: Am I interrupting something?
SPOCK: Nothing but Doctor McCoy's gloating.
MCCOY: Spock, that green blood of yours may have saved you before, but this time it almost did you in. You can't deny it.
SPOCK: I still prefer my physiological structure to yours.
KIRK: Yes, gentlemen, things are back to normal.
MCCOY: He's as stubborn as ever. (laughs)