"May I call to your attention, Captain, that our present course takes us disturbingly near the reported gravitational turbulence reported by Federation ships in this sector of the Orion Arm?" As usual, Spock was both punctilious and logically correct in his assessment of the situation.

Captain James T. Kirk turned in his command seat and glanced at where his Vulcan First Officer was looking at him from the navigation station of the Bridge of the USS Enterprise. Kirk smiled. "I am, Mister Spock. May I call to your attention the fact that Star Fleet Command sent the Enterprise out here to investigate that reported gravitational turbulence?" He looked thoughtful for a moment, then added, "I was told it would be an easy, straightforward scientific exploration mission to make up for the fact that we've seen more than our share of Klingons lately...."

"I was present at the mission briefing, Captain," Spock reminded him.

"Then why the note of caution?" Kirk wanted to know.

"Probably," said Doctor Leonard "Bones" McCoy as he stepped onto the Bridge from the turbolift, "because our Science Officer needs to inject a bit of speculative hazard into a mission that's turned out to be nothing but a boring tour of largely uncharted space. As a respite from continual action, this R&R scientific exploration mission's driving your crew batty, Jim."

"I'll second that," Sulu remarked from the helm. "We've held the same heading now for seven watches...."

Kirk smiled. His people needed the rest and relaxation they termed "boredom." It had been a rough tour out on the edge of the Organian Treaty Zone. Not even a month of shore leave on Starbase 4 had eliminated his own fatigue. And he was certain the rest of the crew was no better off than he.

Kirk had actually looked forward to their current mission: cruising along the inner edge of the Orion Arm, taking data. They were far from Klingons and Romulans. His crew needed the break that a purely scientific measurement and charting mission would involve.

"Be that as it may, steady as she goes, Mister Sulu," Kirk gently told his helmsman. "And don't get too lax. I might become difficult and pull an emergency phaser drill to keep you on your toes."

"The crew would welcome it," McCoy said. "Jim, I know we've had some difficult missions recently, but this crew thrives on such things. Give them a long and uneventful assignment such as this, and they'll go soft on you."

"That I doubt," the Captain of the Enterprise said. "Lieutenant Uhura, you don't seem to be bored."

Uhura removed the receiver unit from her ear and smiled at her commanding officer, a definite breach of her usual efficient Bridge behavior. "Actually, Captain, handling routine communications has been a welcome change. My division needs to regain its proficiency in handling standard, normal procedures again. And do you realize I haven't had to open a hailing frequency even once since we left Starbase Four?"

Kirk chuckled at that, remembering the one time his comm officer almost broke under stress and complained about incessant and repeated opening of hailing frequencies.

"Quite seriously, Captain," Spock persisted, "we are penetrating totally unexplored space where we are not precisely certain of the shape of space caused by gravitational anomalies. The data returned by the Scout Ship Phoenix were quite incomplete because they did not penetrate as closely to the edge of the arm as our course has already taken us."

Kirk sensed that something was bothering Spock. "What seems to be the basis for your concern, Spock? You didn't appear to be disturbed during the mission briefing at Starbase Four. Explain."

"I had insufficient time to thoroughly study the data during that briefing, which was exactly as its name implied: brief. In fact, too brief in relationship to the possible hazards we might face," Spock explained. He turned to the library computer console and called up an image of the galactic sector in which the Enterprise was currently operating. Kirk rose from his seat and came over to Spock's side to get a better view of what his Science Officer was trying to explain. He found that McCoy was at his side as well.

Projected on the screen was the known galactic region from Mark 10D to Mark 25D. The computer image of the Enterprise was shown skirting the inner edge of the Orion Arm about 10 kiloparsecs from Starbase 4. Spock didn't bother to use the electronic cursor to point to what he was talking about; he merely used one of his long Vulcan fingers. "As we already know from our extensive experience in crossing the void between the Orion Arm and the outer Perseus Arm of the Galaxy, there's usually considerable gravitational turbulence at the edges of galactic spiral arms. This turbulence is analogous to that which one would see when mixing a granular material with a liquid using a circular motion."

"Analogous, but not the same, because analogies never bear a one-to-one relationship with the real universe," Kirk pointed out.

"True. However, the Federation has charted the zones of maximum gravitational turbulence in the rift void between Starbases One, Ten, and Eleven and the Outpost Colonies at the edge of the Romulan Treaty Zone...and traffic consisting of both Star Fleet and commercial vessels carefully avoids these zones. There's no acceptable theory concerning the gravitational turbulence on the edges of galactic arms at this time. However, I suspect that such turbulence is caused by the fact that, unlike stellar motions in the galactic arms themselves, stellar motions at the edge of the galactic arms are almost random in nature. In turn, this would produce interacting gravitational fields which, essentially, distort the fabric of space itself." Spock turned to his Captain and added, "Of course, this verbal description is extremely imprecise because of the semantic illogic of our language. I've not yet been able to formulate a logical mathematical model of this hypothesis, but I'd be happy to show you the mathematical model that I've managed to derive thus far, imprecise as it may be at this time...."

Kirk held up his hand. "Spare me, Spock. When it comes to field tensors and translational dynamic matrices, I struggled through them at the Academy and understand them. But when you can get your hypothesis into such a shape that you can explain it in the imprecise words of language, it means you've got your hooks into it."

"I beg your pardon?" Spock put in, raising one eyebrow.

"I think what the Captain's trying to tell you, Spock, is that words sometimes convey a more meaningful explanation of the real world than mathematics," McCoy said with the usual cynical tone in his voice that arose when he confronted the logical Vulcan on such matters. "A long time ago, I learned that mathematics will tell you only the logical consequences of your initial assumptions...and since assumptions are rarely logical, the mathematical results that come from illogical assumptions are garbage."

Spock's other eyebrow went up. "Doctor, I see no reason for you to insult me. I fully realize that you prefer to protect the image of your medical art as an arcane activity not subject to the logic of science, but there are some aspects of the universe quite logically predictable by means of mathematics.... Otherwise, we'd be unable to navigate anywhere in space."

"Gentlemen," Kirk broke into what was obviously growing into another basic philosophical confrontation between his Science Officer and his Medical Officer, "shall we confine such discussions to the ward room, please? Spock, what are you really trying to tell me? Speculate if you have to. But specify." It came out as an order.

Spock reacted suitably. "If we continue on our present heading, we have once chance in three hundred sixty-four-point-six-seven of entering a sector of highly warped space caused by this gravitational turbulence. I cannot predict the consequences."

"As I told you, speculate," Kirk snapped.

"Space may be warped or even folded by gravitational turbulence. We probably wouldn't be able to detect such a folding until we'd crossed it, because our sensors aren't optimized for such work. It would've been more logical for Star Fleet Command to send a properly equipped exploration ship out here instead of a heavy cruiser such as the Enterprise. However, I realize that one does not argue with Star Fleet Command. Because we couldn't detect such a fold in space, we could end up crossing a 'discontinuity' that might transport this ship over very large distances in unknown directions. And it might be very uncomfortable. I'd venture to predict that it might overstress the structure of the ship...."

"And with no advance warning?" Kirk wanted to know.

"Perhaps some indications. As we grow nearer to the zone of greatest turbulence, we could expect to experience some effects."

"Such as?"

The whole structure of the Enterprise suddenly bucked, shuddered, then steadied again. It was enough to throw McCoy to the deck, but both Spock and Kirk managed to grab the console and the bridge rail respectively.

"Such as that, Captain. Only much worse."

Kirk was back at his command seat immediately. "Sections report. Damage?"

Uhura's calm and professional reply came at once over the chatter of intership communications from all departments. "Negative damage, Captain. A few people shaken up."

"Helm and navigation, negative damage," Sulu reported. "Holding course."

McCoy was on his way to the turbolift. "They'll need me in Sick Bay," he muttered, and was gone.

Scotty's voice chimed in over the intercom, "Negative damage in Engineering, Captain. But that was a horrendous jolt! Did we ram something? Or was it a pothole in the road to the stars?"

"I don't know, Scotty!" Kirk shot back. "Stand by. Steady as she goes, everyone." He turned to Spock. "Well, Mister Spock?"

Spock was busy at his library computer console, peering into the hooded viewer. "As I suspected, Captain. A gravitational anomaly due to interstellar turbulence."

"An anomaly strong enough to affect a ship of the size of the Enterprise cruising at Warp Factor Four?"

"Affirmative, Captain. And more to come if we follow this course," Spock warned him. "The Phoenix data are somewhat out-of-date since the stars and the turbulence vortex centers seem to have shifted since they probed this area several years ago. I'd suggest extreme prudence in proceeding further, Captain. I can't predict what we'll encounter in the way of space strains."

When Kirk had to make a decision, he could make one fast. "Sulu, reduce speed to Warp Factor Two, same course. Mister Spock, sensors at maximum sensitivity and range. We'll continue, since it's our mission to explore these gravitational anomalies and chart them if possible. Other ships will follow in our track because this sector of the Federation's territory has yet to be explored and opened to colonization. Lieutenant Uhura, Yellow Alert, please. And have Mister Spock prepare a data dump for transmission to Starbase Four." What Kirk did not add to this was that the data transmission to Starbase 4 was a hedge against the Enterprise running into trouble further along. Under such conditions, the data would at least get back to Star Fleet Command, where it would be available to others.

He punched a control on the arm of his seat. "All hands, this is the Captain," he announced, his voice ringing through the passageways and compartments of the ship. "As you're all aware, we're on a scientific exploration mission that has a good chance of holding surprises such as the one we just encountered. That was only a mild gravitational anomaly, something we were sent out here to chart. There will be others to come. And it's likely to be a bit bouncy. Please secure all frangible materials and fixtures. And be prepared for sudden jolts. We're proceeding at reduced Warp Factor to minimize any future shocks. Carry on."

He punched off the circuit and looked around the Bridge. They were a good crew. Each of them was busy at his post, doing what was required with a cool and professional efficiency. "Mister Spock, will you put on the main screen the computer analysis of space strains ahead based on gravitational sensor findings, please? And steady as she goes, Mister Sulu...."

Captain's Log: Stardate 5064.4

What started out as a restful scientific mission has turned into one with some danger associated with it--as I should have suspected. Any time we venture into uncharted sectors of the Galaxy, we must anticipate and be prepared for the unexpected. In this case, we knew the gravitational anomalies were here, and they've been one of the basic reasons why the Federation hasn't established outposts, colonies, or Starbases across the interarm void in the Sagittarius Arm. We haven't encountered any further gravitational anomalies, but we'll proceed with care, approaching the inner edge of the Orion Arm gradually, taking data as we go. In a way, this possible hazard benefits my crew because they were beginning to become bored and restless with routine. Because this new hazard involves the Enterprise against the universe rather than against hostile life forms such as Klingons, Romulans, and others that we've encountered in the past, it's indeed a form of "relaxation" for us because it's different and allows us to pit our minds against the forces of nature rather than against the forces of alien life forms. Naturally, this is probably most exciting to Mister Spock, who's been engaged in an almost compulsive display of continuing work with the sensors and the ship's computer, taking and evaluating data with what is for Spock an almost feverish intensity of effort. It's been more than ten watches since he's left his post on the Bridge. Doctor McCoy seems unworried about this continued activity on Spock's part, advising me that Vulcans often show the capability to work for long periods of time without what we would consider to be "rest," especially when the activity involves such logical and cerebral work as Spock is now engrossed in.

There were a few more jolts, none greater than the first that had shaken the Enterprise. The crew was almost beginning to get used to them. The first jolt had sent seven crew members to Sick Bay with bruises, cuts, and contusions. The second one caught only two people unprepared. After that, the shocks seemed to become part of the ship's routine, a sudden and unexpected happening that served to keep people on their toes and alert.

Spock was recording and analyzing copious amounts of data. A continuous series of data-dump messages went out over subspace radio to Starbase 4, an activity that kept Uhura busy.

Things had almost settled down to routine again as the Enterprise cruised along the inner edge of the Orion Arm. On one side of her, toward the Orion Arm, the sky was full of stars, while on the other there was but a band of wan light from the millions of stars of the Sagittarius Arm across the 800 parsecs of the interarm void.

Then it happened.

Kirk was resting in his quarters when the wall opposite his bunk appeared to shimmer and wave as if it had been made from gelatin. He felt a burst of nausea pass through his body such as he'd once experienced when he'd been through a transporter that was badly out of phase. The next thing he knew, he was flattened to the overhead, then dropped roughly back into his bed with a thump that caused the bunk supports to complain with a groan of stressed material. There were other noises that accompanied this severe overload of the ship's gravitational-field generators, noises from both the ship and the crew that penetrated the bulkheads of his cabin. Groggily, sick to his stomach, and very much shaken, he rolled to the floor and managed to stand up. He slammed his palm down on the wall intercom switch.

"Bridge, this is the Captain. Report!"

The intercom was dead.

Only then did Kirk realize that the emergency lighting was now on. He staggered as the ship's internal field struggled to reestablish itself again. When he got to the door to his cabin, it wouldn't open; he smashed the emergency latch cover and opened it manually.

The ship's corridors were full of moans, cries of pain, and screams of anguish. Kirk shut them out of his mind; he couldn't stop to help any of his crew right then; he had to get to the Bridge. The paramedic crews from McCoy's department would be along soon to take care of the injured. Kirk had the entire ship to worry about.

The turbolifts were not operating, so Kirk resorted to the companionways and gangways. It had been a long time since he'd entered the Bridge through the emergency doors, which he had to operate manually. What he found when he stepped onto the Bridge was disarray.

Sulu was sprawled on the floor beside his post. Uhura was also injured, holding her elbows and trying vainly and valiantly to respond to distress signals and calls coming into her station from all over the ship. Spock had taken over Sulu's post next to a battered Ensign Chekov, who was bleeding from a deep cut across his forehead. Scotty, with his uniform tunic torn, was desperately working at the engineering station.

Kirk knelt next to Sulu momentarily, only long enough to learn that his helmsman was still breathing. Then he snapped to Spock, "Report."

"Extreme gravitational anomaly," Spock managed to get out. "Actually, a 'fold' in the fabric of space, so to speak. There was no way to tell that it was coming, because we have no sensors that can detect such a thing."

"Injuries?"

"We don't know. The ship's fields went down momentarily, actually reversed themselves, then came back. Communications are out in some sectors of the ship," Spock fired back.

"Uhura." Kirk got to her side. "Anything broken? Are you badly hurt?"

"I...I hit the ceiling," she mumbled. "When I came back down, I landed on both elbows. I wasn't ready for it...or I would've relaxed and rolled with it.... I don't know if anything's broken.... My arms just hurt terribly...."

Kirk punched a button on her panel. "Sick Bay, this is the Bridge. McCoy?"

"Jim, I'll have a team up there just as quickly as I can," McCoy's harried voice came back. "There're injuries all over the ship." And the circuit was cut from the other end.

Kirk did not react to this curt reply from his medical officer. He knew that McCoy was under terrific pressure at the moment. There'd be a paramedic team to the Bridge as soon as McCoy could get things organized.

Yeoman Rand appeared through the emergency exit of the Bridge. She was disheveled but apparently unhurt. "Yeoman, are you all right?" Kirk wanted to know.

"Yes, sir. I thought I would be needed most here," Janice Rand replied.

"You are indeed. Take over emergency medical aid to Uhura, then Chekov, then Sulu," Kirk ordered. He turned to Scotty, knowing that Janice Rand would handle the Bridge-crew injuries without further attention from him.

"Scotty, engineering status report," Kirk snapped.

The engineer was shaking his head sadly as he took reports coming in from his engineering department. "Minor damage to the ship's structure, Captain. We have life support, impulse power, and one warp drive unit functioning. There's considerable damage to the second warp drive unit, the full extent of which I dinna know yet."

"Can we make warp speed?" Kirk wanted to know.

"Aye, but with only one unit, the best I can give ye is Warp Factor Two...and that's full-out with the good unit wide open...and subject to possible breakdown, since I haven't had the chance to check for possible damage there," the Engineering Officer replied, not looking up from the engineering consoles.

"Mister Chekov, take the helm," Kirk ordered. "All engines stop. Let her drift in space until we find out where we are. Mister Spock, give me a position. Where are we?"

Spock moved from the helm and walked back to his library computer console. Kirk joined him, watching his first officer bring systems back on line and check them out. "Captain, the Stellar Inertial Navigation System has completely lost alignment. We still have the galactic time base pulse in operation, and the course record and data banks appear to be secure. I maybe able to reconstruct what happened. But as you can see, the course-record data bank indicates a major discontinuity."

"Which means that somehow the Enterprise has jumped through normal space," Kirk added.

"Quite correct. As I pointed out earlier, the gravitational anomalies in this area could create what amounts to a fold in the fabric of space," the Vulcan continued. "According to the data here, that is exactly what has happened. We were thrown across such a fold in space, caused by an extremely strong gravitational anomaly, almost like jumping through a black hole or Dirac discontinuity."

"Spare me the theory, Mister Spock. Right now, I need to know where we are," Kirk told his First Officer, his first thoughts being of the ship and its crew. "We can run over the theory later when we know where we are and where we're going."

"I'll put a visual panoramic scan on the main screen," Spock remarked. He then addressed the ship's computer in the verbal command mode, "Computer, scan and analyze the visual, ultraviolet, and X-ray spectra of the stars in the panoramic sensor scan. Match and identify any known star groups and give me a hard copy printout of same. Store the data for possible use in realigning the SINS."

"Working," the computer's vocoder-created female voice replied tonelessly.

Kirk turned to watch the scan on the screen. "Let's have full magnification and image intensification, Mister Spock. It doesn't look like there are any stars out there at all."

And there weren't.

At full intensity, the best the scanners could pick up was the faint band of light emanating from the stars in the galactic plane.

"Reporting," the ship's computer voice said. "No known star groupings are recognized. Further instructions, please."

"Computer, run analyses of selected star groups assuming a ship displacement of several hundred parsecs toward the center of the Galaxy and adjusting stellar parallax accordingly," Spock ordered.

"Working."

"Are we still in the Galaxy, Mister Spock?" Kirk wanted to know.

"Affirmative. I have the Shapley Center identified," Spock remarked, gazing into the hooded viewer of the library computer console. "But there's considerable interstellar dust along the plane of the Galaxy. Therefore, I'm having great difficulty identifying any known star groups. I'll need at least two recognizable stellar reference points in addition to the Shapley Center before we can realign the SINS."

"But where in the Galaxy are we?"

"I can't give you a precise answer yet, Captain."

"Speculate, then."

"Very well. We jumped an estimated distance of about three hundred parsecs, and we appear to be in the void between the Orion and Sagittarius Arms. This is totally unknown and unexplored space, Captain. I can't locate a single individual star at this time."

Yeoman Janice Rand stepped up to Kirk and reported, "Sir, I've stopped the bleeding from the cut on Mister Chekov's forehead, and Lieutenant Uhura's arms appear to be only bruised, not broken. I gave her a mild analgesic injection into each forearm. That will ease the pain until Doctor McCoy can make a professional examination. But we'll have to get Mister Sulu to Sick Bay as quickly as we can get a medical team up here."

"How about it, Lieutenant?" Kirk asked gently. "Can you continue to run your post temporarily?"

"Yes, sir. I hurt, but not badly enough to ask to be relieved."

"Good. First, raise Starbase Four and report what's happened. Then get me a summary of internal damage and injury reports."

"Right away, sir." Although Uhura's face showed that she was indeed injured, she stuck to her post, inserted the receiver in her ear, and began to attempt to communicate with Starbase 4.

"Three hundred parsecs," Kirk mused, doing the calculations in his head. "That's a long trip at Warp Factor Two...."

"One hundred twenty-two-point-two-five real-time years, to be precise, Captain," Spock put in.

"And that's just to get out of this void and back into the Orion Arm," James T. Kirk added. "Scotty, we've got to get that warp drive unit repaired and back on line."

"Aye." The Engineering Officer nodded. "We can't crawl across the galaxy with only one unit working. We'll all be old and gray by the time we get back to Starbase Four."

"What will it take to fix the warp drive unit?" Kirk wanted to know.

"I canna tell ye yet," Scotty replied. "My first priority is to make sure that all internal systems are functioning, and we've just about got everything back now. I'll get to work examining the warp drive unit. I'll have an answer for ye shortly."

The doors to the turbolift swished open, and Bones McCoy entered with a team of four paramedics.

"Well, it's about time," Ensign Chekov remarked.

"Half the crew injured, most of the turbolifts out, and you expect ambulance service?" McCoy snapped, obviously under pressure and rushed to a far greater extent than he liked. He looked around. "Who's hurt here?"

"Better get Sulu down to Sick Bay right away," Kirk pointed out. "And Uhura and Chekov both got banged up."

McCoy was at Sulu's side at once, his medical sensor out and checking the Helm Officer. "You're right. He's got internal injuries. How about you, Uhura?"

The Communications Officer was busy at her console, and she didn't hear the doctor's question. McCoy walked over to examine her, and she seemed oblivious of him. Finally, she spoke to Kirk. "Captain, I'm sorry, but I can't raise Starbase Four. In fact, I can't raise anything on subspace frequencies, not even the usual data exchange buzz or the ship-to-ship channels. Nothing but Jansky noise and subspace whistles."

"Which means I'd better get busy on that drive unit or we'll be out here in the middle of nowhere forever," Scott remarked, heading for the turbolift. "I'm going down to Engineering, Captain. I'll let you know the status of the other drive unit as quickly as I can." And he was gone.

Kirk looked at his First Officer. "Spock, I hope you can get that SINS unit aligned again. In the meantime, Mister Chekov, put the Shapley Center on our stern and hold a course directly away from it back toward the Orion Arm. Make Warp Factor One. I don't want to overstrain our remaining warp drive unit."

"Aye, aye, sir."