On the USS Enterprise, the crew is at full alert, for Starfleet Command has received intelligence of a Klingon warship in the sector. The Captain is on the bridge and Lt. Sulu, Mr. Spock and Lt. Uhura are all at their stations. The Enterprise is returning to base at warp factor 2 with the shield up.
"Mr. Spock, our new orders from Starfleet mentioned 'cloaking'; do you know what that is?"
"Yes, Captain; the Klingon Empire has been experimenting with a means of making its warships difficult to detect. Reports say they can be rendered invisible to normal scanners. We on the other hand, with our deflector shield at full strength, will be clearly visible even at a considerable range."
"That is deliberate. Starfleet believes that this warship has been fitted with 'cloaking.' By cruising along like this we hope it will reveal itself by attacking us. They won't be able to resist a 'sitting duck'."
"Your simile is a strange one, Captain, but if I interpret it correctly then that is close to our actual state. We have only one photon torpedo left and problems with the warp drive; the Enterprise is not battle ready."
"Not for a prolonged engagement, no. The plan is to gather what intelligence we can and then make a run for home as fast as our dilithium crystals permit." The Captain turns to Mr. Sulu. "Helmsman, are the phaser banks fully charged?"
"At 90%, Captain," replies Sulu.
Kirk flicks a switch on the arm of his command chair. "Engineering room, this is the bridge. What is your status?"
"Scotty here, Capt'n. The dilithium crystals are holding, but the full shield is putting a strain on them even at this warp speed."
"Scotty, if we had to get out of here in a hurry what speed could we manage?"
"With a half shield we should be able to maintain warp 4 for perhaps an hour."
"And in a real emergency?"
"We'd be lucky to get to warp 6 before they blew. Then we would be down to impulse engines and a low-level shield. Any Klingon ship could blow us out of the water!"
"OK, Scotty; keep nursing those crystals. Mr. Sulu, maintain course but drop to warp factor 1.5."
"Aye, Captain; warp factor 1.5 it is."
"Lieutenant Uhura, are you monitoring for any Klingon communications?"
"Yes, Captain; on all frequencies."
"Have you heard anything?"
"Negative, Captain."
"Mr. Sulu, have your detectors shown anything?"
"Negative, Captain; both short and long range detectors show nothing across all energies."
"Mr. Spock, what are your recommendations?"
"If I understand early military terminology, 'steady as she goes'. Do I have the correct idiom?"
Before Kirk can reply, there is a cry from Sulu. "Captain, I'm seeing faint signs of a warp drive; I'm trying to get a fix on it."
"Could it be Klingon?"
"Sorry, Captain, it's gone again."
Kirk thinks for a moment. "Chances are that there is a 'cloaked' Klingon ship out there; it has seen us and may be preparing to attack."
"Affirmative, Captain," says Spock. "They will have noticed that our deflector shield is up and are wondering whether to venture an attack."
"See if you can locate them, Spock. Meanwhile, we'll carry on as if nothing has happened."
For an hour, nothing happens and no further sign of a Klingon ship is detected. Kirk decides to pretend that the Enterprise is short of power. "Drop our speed to warp factor one. Lower the deflector shield to half power."
A few minutes later, Sulu is able to report. "Sensors are showing that warp drive again, Captain. It is to our stern and seems to be following us. It's too faint to identify. There's nothing visible."
"Nevertheless," says Kirk, "bring up the rear view on the main screen. Prepare to fire phasers."
"Aye, Captain."
Everyone on the bridge, except Mr. Spock, stares at the screen expectantly; only distant stars can be seen. Then Uhura breaks the silence. "Captain, we are being hailed; voice only." She switches the call through to the speakers.
"Federation ship, you cannot see us, but you know we are here. Our weapons are trained upon you. You have two minutes to surrender your ship or it will be destroyed. EOT"
This ultimatum is relayed throughout the Enterprise. Scotty shakes his head over the dilithium crystals and goes to see what can be done with auxiliary power sources. The order for battle stations is heard, and in the medical bay Dr. McCoy mutters under his breath. The one remaining photon torpedo is primed and made ready to fire. On the bridge, meanwhile, Captain Kirk has given the order to increase the deflector shield to maximum. "Mr. Sulu, Mr. Spock, can we pin down the location of that ship?"
"It is very unlikely we would strike it with our phasers, we will have to wait until it reveals itself," says Spock.
Surprisingly, the Klingon ship does just that, fading into view before their eyes. It is a light cruiser. "Fire phasers!" yells the Captain. He is blinded by a violet flash – not white or red but plain, uniform violet across his whole field of vision. Then a massive jolt, total darkness and complete silence follow. Groggy at first, he cannot tell whether he has been unconscious, but becomes aware that others on the bridge are calling out to each other.
"Kirk here; is anyone injured?"
"Spock speaking, Captain. Everyone on the bridge is accounted for. No injuries sustained."
"What happened, Spock? What is our situation?"
"We are alive and have air pressure and gravity. All ship's systems are down. If the emergency lights do not come on soon, then our situation could be serious."
"Because we can't see anything?"
"Because it means that the ship is dead."
"Any theory as to what happened?"
"None yet, Captain, but I am wondering what happened to the Klingons. We are helpless; why have they not finished us off?"
"I have been thinking the same thing. … Mr. Sulu, do you have any ideas?"
"We did fire one phaser burst, Captain. Perhaps they too are crippled?"
At this point, the first emergency light comes on. It seems bright after the Stygian darkness they have been in. Other emergency lights follow. Captain Kirk permits himself a sigh of relief: they might get out of this alive. "Spock, how long before we have internal communications?"
"That should come next, Captain."
Right on cue, there is a crackle. "This is Scott in engineering. Are you there, bridge?"
"Kirk here, Scotty. We currently have emergency lighting but nothing else. Can you give me a report?"
"All I know for sure right now is that we suffered a sudden and total loss of all power and that emergency backup is beginning to switch in. I'll report again when I know more, Capt'n."
Over the next few minutes, various sections report in to the bridge. There are only minor injuries to crew, but bulkhead doors remain sealed and movement around the ship is limited. Scotty calls the bridge.
"Capt'n, main auxiliary power has been restored, and most systems should be online shortly. This will restore control to the bridge. There's very little sign of damage. That's the good news. The bad news is that one of our remaining dilithium crystals has perished. That means no warp drive, no deflector shield yet, and no way to recharge the phaser banks."
"Thanks, Scotty. Can anything be done for the shield? Will we have impulse engines?"
"I'm working on the shield now, Capt'n. If there's no damage to the engines, you should have power in a few minutes."
"What about the transporter and the ship's computer?"
"The computer should be available to you very soon, Capt'n. And they're starting to run tests in the transporter room now."
As more and more systems come back online, activity on the bridge grows frantic. They establish that the Enterprise's hull had not been breached and that damage is minor. They are in a star system and close to an earth-like planet. There is no sign of the Klingon cruiser, but they have no way of knowing if it is near and 'cloaked'. Lt. Uhura is unable to receive any signals or make contact with Starfleet Command. Yet, both she and Mr. Spock are certain that the Enterprise's comms are operational.
The phaser bank is totally depleted, and their only weapon is the one remaining photon torpedo. Mr. Scott reports that the impulse engines are ready for use, but the deflector shield remains down. He confirms that without at least one new dilithium crystal, the warp drive cannot be used.
Captain Kirk orders that the impulse drive be used to put them into orbit around the planet. He again asks Spock for any explanation of what has happened to them.
"Captain, we are far from the position where we were struck. The ship seems to have been hit by some new Klingon weapon. I noticed a purple flash before the blackout; that was something new to my experience."
As they approached the planet, Spock scans it. "That is odd. Captain, the scanner shows many tens of millions of humans on that planet."
Uhura is unable to detect any transmissions from the planet. Meanwhile, the Captain has been examining its image intently. "Mr. Spock, that planet looks very much like Earth. We must have some record of it!"
"Most remarkable," says Spock. "This system matches the Solar system precisely. …That is Earth."
"There must be some mistake!"
"There is no room for doubt; the fit is exact. That is Earth and the Moon."
"Then what has happened? There are no visible lights, no radio transmissions, no artificial satellites. And didn't you say the population was only 'many millions'? There must have been some unimaginable catastrophe!"
"There is another possible explanation, Captain. Whatever happened moved us both in space and time; we have been thrown several hundred years into the past."
"Is that possible?"
"I have set the ship's computer to take astronomical measurements and determine the date. Then we will know."
Within the hour it is confirmed: the data precisely fit the year 1790 AD.
"Spock, is there any way back – to our own time I mean?"
"The only known way is to sling-shot the Enterprise around the sun. For that we need warp drive."
"And for that we need dilithium! Is there no other way?"
"None, Captain, and there is no way we can wait nearly five hundred years."
"We can't expect to be rescued either. Is there any source of dilithium within the Solar system, any source at all?"
"Mr. Scott has been looking into that, Captain. He says that a few, poor quality crystals are to be found on Earth itself. We won't know if they are of any use until we find one."
"Captain, permission to speak," says Sulu. "Could we send or leave a message for Starfleet Command to find at the right time? They could send back dilithium crystals for us to use."
"Spock?" asks Kirk.
"The sling-shot technique cannot be used to travel back so far into the past. However, we got here, so others can follow. They might baulk, though, at vaporizing a cruiser in order to try."
"Vaporizing!"
"Correct, Captain. The evidence suggests that the violet flash we all saw was the Klingon cruiser being converted to white-hot plasma. Without the deflector shield, the Enterprise would have been destroyed. Instead, we were hurled away in space and time. I can only surmise that our phaser strike revealed a fatal defect in their cloaking device."
"Nonetheless," says Kirk, "We can still try that avenue. Mr. Sulu, come up with some ideas as to how a message might be delivered at the right time."
"Aye, sir. But I am wondering how we ended up so close to Earth, the odds must be astronomical!"
"Not necessarily," says Spock. "We were traveling on course for the Solar System when the event occurred."
"We can afford to marvel at our good luck once we are safely back in our own time," scolds Kirk. "Mr. Spock, we must look for dilithium on Earth; that seems our best chance. Does Scotty know where to look?"
"There are several likely locations in the Earth's crust. If we concentrate on areas where mines have already been dug, then the optimal is in Britain, a place called …" He consults his notes, "Corn Wall."
