Chapter Eleven
The Secret Train
...
The protective field over the stairs of the shielded terminal had momentarily collapsed when the Yr came flying out from within. With the Yr now gone, everything was back in place. Aislynn was immensely relieved to see that in all of the excitement, no one seemed to have spotted the hidden opening for those few brief moments. Police whistles started to shrill just as they crossed the landings, but they ignored them and hastened to the hidden entrance.
Holmes was almost vibrating with excitement, taking the steps two at a time as they descended. When they reached the bottom and entered the station, he stopped, staring in wonder at the train. His face collapsed into a scowl as his eyes swept over the tumbled, disintegrating cubes that littered the ground and the scarred, burn-marked state of the train itself.
"You didn't mention that it had been through combat," he accused, frowning at Watson.
"We were a bit busy at the time," Watson replied, seemedly unperturbed by his friend's demeanor.
"Dreadful battle," Holmes murmured, stepping forwards to examine the engine minutely, before moving on to the cars. Just as before, the cubes instantly crumbled to powder at the slightest touch.
"And ultimately a futile one, at least for the defenders," Taydin looked very grim, his fingers on one of the scorch marks. "These were probably produced by photon-lens blasters; no photon-based technology has a prayer against a Yr."
"You still have not explained what the Yr actually are," Watson pointed out, as he turned and frowned at Taydin.
The Scout Commander stepped back from the carriage he had been examining and turned to focus on Doctor Watson, his dark eyes shadowed by things Aislynn knew the human could never imagine, let alone comprehend.
"The Yr are creatures that no one knows much about, not even the Time Lords," the dark haired Scout informed him.
"Time Lords?" Holmes interrupted, pouncing on the words like a cat capturing a juicy mouse.
"That's us," Taydin explained, pointing at himself and Aislynn.
"Because Time Kings must have already been taken," Watson snarked under his breath and Katie, Jake, and Owen snorted in amusement.
"Whereas those two?" Holmes asked next, indicating Jake and Diana and pointedly ignoring Watson's commentary.
"A bit more complicated," Aislynn sighed. "A cloned and altered Gallifreyan and a human who has been re-engineered to match her."
"Gallifreyan?" asked Holmes sharply.
"Our species begins as Gallifreyans," Aislynn explained, frowning in concentration as she tried to explain things far outside of the detective's understanding. "Time Lords are what happens when Gallifreyans are exposed to a particular form of energy."
"Ah," Holmes mumbled, eyes half-shuttered as he pondered this. "Go on!" he urged.
"Right, the Yr are extra-dimensional entities and have only been encountered in three-dimensional planes of existence a handful of times. However, from these encounters, we do know a few facts," Taydin replied.
"A very few," Aislynn added grimly.
"First: a Yr is an… an angular entity, for lack of a better word. While it can probably move around quite freely in its two-dimensional home plane, when it intersects a three-dimensional plane, it must remain tethered to one of those two dimensions," Taydin continued.
"Yes, we saw that upstairs," Watson said. "It moved along cracks in the pavement, and the mortar between the bricks."
"Always along parallel planes, or at ninety degree angles," agreed Taydin. "Did you notice how we first encountered it in that corner? Corners are the intersection of three ninety-degree angles, and are particularly powerful. The demarcation point of a concave corner represents a weak spot in the three-dimensional plane, at least as far as a Yr is concerned. Concave corners can be used for Yr teleportation."
"It hit a big speed boost once it hit the stairs," mused Diana.
"Stairs by their nature involve a lot of corners," Taydin explained. "What you encountered there was a phenomenon known as the Intersection Acceleration Scale. I gather it was following the lines of the underground rails once it hit the tunnel? You never would have caught it if there hadn't been a curve."
"Speaking of which, what about the Miraculous Transforming Wonder Ball?" Diana interrupted, showing it around. It was the same ball as before, but now had a distinctly golden tinge, and felt a good deal heavier.
"May I see that?" Taydin asked, and Diana handed it over, while Aislynn took over the explanations.
"The 'Wonder Ball,' as you call it, was an example of another Yr-related phenomenon: Spherical Repulsion. It didn't have anything to do with the ball, itself. It had everything to do with the fact that the ball is a perfect sphere. Spheres, by mathematical definition, are shapes that contain no angles. Even if the ball hits, and flattens out a bit at that moment, it is still all curves. With one notable exception, Yr do not do well with curves." She smiled at Diana. "In essence, when you put the ball inside of it, at least if the Yr can be said to have an inside, you choked it. It drowned."
"The substance of the ball has now been changed from the multidimensional contact," Taydin added after a brief scan, and handed it back to her.
She handed it to Jake to inspect, and from there it got handed around as everyone wanted to take a look at it.
"And the exception?" prompted Holmes.
"I beg your pardon?" Aislynn replied.
"You said that Yr don't do well with curves, with one notable exception. What is the notable exception?"
"Yr feed on imperfect curves," Aislynn said, giving Holmes a meaningful look. Her tone indicated that this statement had some significance, but Diana shook her head, clearly not understanding the reference. Holmes, however, had an expression of dark realization, and templed his fingers, his eyes burning blackly as he studied the train.
Katie, who had been the last person to examine the ball, offered it back to Diana, but Diana was distracted with the question of imperfect curves, and with watching Holmes, who was stalking up and down animatedly. With a shrug, Katie dropped the ball in her nurse's bag.
"I don't get it," Diana frowned.
"Organic creatures, such as ourselves, are essentially large collections of imperfect curves," Aislynn explained. "A Yr can consume those curves, just as a person would eat a meal."
"So… if it eats all of your imperfect curves… what happens to you?" Katie asked, looking like she had already guessed the answer and didn't like it much.
"You lose your curves and collapse into a series of cubes. That's not generally a process that organic creatures can survive."
There was a silence after this, as everyone digested this thought, staring at the train and its grisly contents.
"What about convex corners?" Holmes said intently.
"Would someone please explain what a convex corner is? And a concave corner for that matter?" Diana scowled.
"A concave corner is a corner that points inwards; any of the corners in this room would be considered to be concave corners," Aislynn replied. "A convex corner would be a corner that points outwards. Cube shapes, such as dice or sugar cubes, have eight convex corners."
"Yes, yes," Holmes said impatiently, "But, what is the significance of convex corners?'
Aislynn hesitated for the briefest fraction of an instant.
"Any three dimensional shape that displays convex corners can be used for multiplication," she said. "Cubes, of course, fall into this category, along with most of the hedron series: tetrahedrons, octahedrons, dodecahedrons, and so on."
"Yes, we've all taken Geometry!" Holmes muttered. "The point it, what it about these corners that allows them to speed up and slow down and how can we stop them from killing anyone else!" He was glaring at the train as if it had personally offended him, daring to chug into London in defiance of physics and logic.
"And multiply," mused Diana. "So… they multiply at points that stick out, but they're repelled by ball shapes… what about Myra?" From the look on her face, she was mulling over an idea.
"Myra was certainly a victim of a Yr attack."
"Which means that there was one already present in London prior to the arrival of this transport," pointed out Taydin grimly.
"Mmm, point," Aislynn was frowning at this.
"Why didn't you say that at the warehouse? Or in the cab?" Owen was frowning at them both.
"I didn't say anything, because I wasn't sure," Aislynn responded. "I am sorry to say that there are things other than the Yr that are capable of reducing organic creatures into mounds of small cubes."
"Seriously?" Jake protested. "There is more than one way to end up a pile of sugar cubes?" He looked aghast at the thought. "I will never look at a sugar bowl the same way again."
"Agreed," Watson mumbled, peering at the cubes with wary eyes.
"Unfortunately, yes, yes, there is. I also ought to emphasize just how unusual a Yr encounter is," Taydin added. "One doesn't generally start looking for a zebra the moment one spots hoof prints. At least not in Europe."
"The emergency transport encountered a Yr, then. Or, more than one… what is the plural of Yr, anyway?" Katie asked.
"The plural of Yr is Yr," Taydin responded. "And yes, it is possible that they could have encountered more than one."
"Where did the emergency transport come from, anyway?" asked Owen.
"An excellent question," Taydin muttered and headed to the front of the train. "The piloting station ought to have logs that map out the route. If we can read them, then we'll know."
"It'll be up here," Aislynn strode purposefully up the length of the train. The first car appeared to be the engine, just like on a human built train. The second, which was empty and flat, had no visible use, but Aislynn suspected that it was some sort of battery for the engine.
The third car looked like a passenger car, but had far few windows than the other cars. The doors looked more secure and were of a different style, square and straight, as opposed to the graceful, slightly-curved tops of the doors in the passenger cars.
She pointed her sonic at the door and it gave a satisfying 'click' noise; but when she grasped the handle and pulled, it didn't so much as budge. She scowled and pulled harder, putting her weight into it, but it still refused to open.
"Jammed?" Taydin asked, putting his own hand beside hers and augmenting her Time Lord's strength with his own.
It creaked and groaned on hinges that hadn't moved for unknown periods of time.
"Barred from the inside," panted Aislynn.
"Good thing I brought toys!" Diana enthused and, with a huge grin on her face, pulled out a tiny laser cutter.
"Wait, how did you get that through the teleportation here? None of my stuff came through!" Jake protested.
"Oh, I had it disassembled, I was fiddling with it on the way out and had forgotten to put it back together," she explained with an airy wave. "So, let's see what this baby can do!"
"That's my Angel," quipped Jake with a grin as the Time Lords cleared out of the way.
Diana got to work, mumbling to herself.
"Here it is," she said after a few minutes. "Yes, it's a bar, I think… you guys better stand back, they could have booby-trapped it or something, you know." She didn't seem the least frightened by such a prospect.
"Madam, you have a terrifying imagination," Watson sighed, though he moved with alacrity to the rear.
"Nah, I have just been doing this sort of thing a while," explained Diana, but then paused, frowning at him thoughtfully. "Didn't you say you went to Afghanistan or somewhere? As a war doctor? Didn't they have bombs and mines and things?"
"I was a doctor, not a soldier. I patched up those who faced such horrors," he explained gently. She turned to study him, her face filled with compassion and understanding.
"You'd like Susan, a friend of ours. She was a doctor in a war too, but I was a soldier," she said simply, as she got back to work. "Well… sort of." There was a distinct clang noise from within the car. "Ha! There it goes." She grasped the handle and pulled.
"Perhaps I could have a conversation with this Susan that made sense," Watson sighed, but Taydin shook his head.
"Doubtful, her opinion of Victorian era medicine was not... high," he explained and then peered forward to see the door.
"And Katie, Owen, Jake and I make sense!" Diana protested, but then took her first look behind the door. "...Oh."
"Of course you do," Watson replied politely, not yet having seen what Diana was looking at. Taydin winced and looked at Katie and Owen.
"Perhaps you could wait here, it's... cramped inside," he explained and they nodded.
Diana stepped back politely, but her face was solemn. Holmes moved forwards briskly, seemingly unfazed, along with Taydin and Aislynn.
"This was where they made their last stand," Holmes said, his eyes sweeping the area as he studied every detail. "Please wait a moment, while I examine the room."
They all paused and then watched Holmes as he pulled a magnifying glass from his pocket and began examining every inch of the compartment. He was incredibly thorough and Aislynn was astounded at his energy, he was like a terrier on the scent, crawling about and peering into every nook and cranny.
"Wouldn't it be easier for you two to use the sonics to analyze the room?" Diana whispered.
Aislynn shook her head, very surprised at the suggestion.
"Diana!" she said. "This man is an artist! Any information from our sonics would only serve to complement his efforts… one mustn't underestimate the value of the human touch at such moments."
"The sonics can give us data, but Mr. Holmes is a pure reasoning machine capable of leaps of intuition and insight that no computer can ever hope to achieve," Taydin replied softly.
"Ha! Indeed. Good to know that I won't be made obsolete by technology," Holmes chuckled, even as he continued to work.
"Actually," Katie offered, "The histories of your investigations were preserved and enjoyed even in our time."
"Doctor Watson's stories about you inspired many of the police's techniques for centuries afterwards, including your forensic and chemical investigations. You changed the entire methodology of criminal investigation," Jake murmured. "Not that I should probably be telling you that."
"I suppose I ought to keep writing your cases up then," Watson teased. "As dramatic and silly as they are, they seem to become quite useful."
"I will never live that down," Holmes groaned and then popped back up to his feet and turned to gaze at them. "So! I deduce that there were either twenty-seven or twenty-eight individuals inside this room, based on the average mass of a human being and a simple calculation of the number and size of the cubes. As there are no partially crushed cubes, as there would have been had there been some survivors, they all died within moments of each other. I lack data on how quickly the Yr can kill one victim and then move on to the next, but I suspect that multiple Yr is the most likely answer. However, as there are no observable tracks and we have found no further Yr in the area, an exact number cannot be precisely calculated. The survivors had warning, as they barred the door, and as the greatest volume of cubes is located in that far corner, where they probably huddled, prior to being consumed."
Aislynn shivered. Her imagination was quite capable of showing her how terrible the end they had come to was. Taydin looked grim beside her, but they both remained focused on the whippet thin man in front of them. Holmes turned and indicated the rest of the room.
"None of the equipment appears to be damaged, beyond the simple ravages of time, whereas the entry door shows heavy fire. The bar across the door was a makeshift device. You can see from the joins and sloppy workmanship that this door was certainly not meant to be barred in this fashion. They were truly desperate at the end." Holmes' own expression was thoughtful as though no part of the tragedy touched him, even though Aislynn could sense his own burning anger at the tragedy, he kept it far away from his thoughts, allowing no part of his emotions to cloud his judgement.
"May I check the logs now?" Taydin asked, gesturing at the panels at the far end of the room.
"Of course, I have seen all I needed to," Holmes agreed and then frowned, pacing as he thought. "What defenses can one mount against these Yr?" he suddenly asked.
"Bouncy balls seem to work well," Diana pointed out. "And if we're talking about round things… have you guys invented bullets yet or do you still use lead balls?"
"We have bullets," Watson answered a trifle stiffly. "We have machine guns, you know."
Diana looked somewhat embarrassed.
"No, I don't know," she protested. "I just got here! I never learned about Victorian London, I don't know any of this stuff! That's why I was asking!"
"He meant no offense, Miss," Holmes told her, his deep, penetrating eyes focused on her with a laser-like intensity. "He knows as little of you as you do of us, after all. Your lack of education and your existence as a slave was not being mocked by him. It is nothing to laugh at."
"Wait? Slave? What are you talking about Holmes?" Watson interrupted, looking horrified. "I do hope that I didn't offend you! I did not mean to at all!"
"No, not in the least, I thought I had offended you," Diana said, rubbing the back of her neck awkwardly.
"I was getting tired of being confused and treated as though I was slightly dim. I am sorry," he explained, looking chagrined.
"Oh, I know exactly what you mean," Katie commented, even as Diana opened her mouth and closed it again.
"No kidding!" laughed Owen. "My head was spinning for weeks when I first ran into this! Every other word was like some foreign language!"
Aislynn was looking back and forth at everyone.
"I am so sorry," she apologized to them all. "I never meant to treat you, any of you, as if you were dim."
"Look, you don't mean it, and we get it," Diana added. "But you get involved in stuff, you know you do, and then you get all excited and it's like you're way out there at the end point and you forget that we don't have any of the middle bits, you know?"
Aislynn had no idea of what to say.
"It's because you love math," Diana nodded wisely at her. "The rest of us… we've basically made peace with math, more or less, but we don't love it, per se."
"All of which is fascinating, no doubt," Holmes interrupted impatiently, "But, does not get us further along to finding the Yr!"
"Yes, of course," Taydin agreed. "Let's get this computer running." He knelt beside the panel and pulled out his sonic, working carefully to activate the panel without disturbing the cubes.
"Actually, speaking of defenses against the Yr," Aislynn said, turning to Holmes, "Shall we take a look at the defenses which are already in place? Watson mentioned earlier that if you walk into these train tunnels you come out again from the same tunnel, was that correct? That should mean that a shield is already in place. I'd like to see what sort of shape it is in. While we work to determine that, Taydin should be able to pull the information from the terminal by the time we return."
"Yes, go ahead," said Taydin. "This is going to take me a few minutes."
"Very well," Aislynn said, and made her way to the doorway. There was a point on the platform with stairs down to the level of the tracks, and she descended these with purpose. "I gather you have tried all four of these tunnels?" she prompted Holmes. "All with the same result?"
"Of course," Holmes nodded.
"Well then," she said, "Let's see why." She thumbed her sonic, causing it to produce a soft light, then headed down one of the tunnels. "How far in does the phenomenon occur?" She quizzed Holmes.
"It's a torch as well?" Watson marvelled, staring at the sonic in fascination.
"Focus, Watson!" Holmes scolded. "It starts about three hundred yards in. I haven't been able to make a more precise determination," he didn't look at all pleased with that.
Aislynn nodded and headed down the tunnel without further comment.
The tunnel was surprisingly dark, and the air seemed soft and still. The noises from the platform dropped away at once, as if a curtain had fallen over the opening. Pipes lined the walls and the tracks gleaming in the dim lighting in the center of the tunnel. Smoke from a thousand trains had blackened the walls and ceiling, making the light dimmer still.
Within a minute or so, Aislynn's sonic began making soft pinging noises. At first the pings came long seconds apart; but as they continued to walk on, the pings began coming more frequently.
"Definitely shielded," she mused thoughtfully. "There's bound to be a maintenance panel about, let's see….." She began walking briskly down the dark brick tunnel, following the signals from her sonic.
Once the pale half-moon of light from the tunnel had almost faded away, and the pings were tumbling on top of each other in their eagerness, she stopped, raising the sonic and sweeping it across the space, looking for the source.
"Ha! Here we are," she walked to one of the walls, removed her gloves and pocketed them. With deft fingers she felt carefully along the soot-stained wall, while tracing along with the sonic in the other. After a few minutes of fumbling about in this manner, a faint square outline appeared on the wall, glowing softly amber.
"That's it," she said, but she didn't look pleased.
"I can't imagine how you missed something so obvious," teased Watson.
"Despite what you would lead your readers to believe, Watson, I am merely human after all," Holmes replied in a dry tone.
Aislynn reached to the bottom of the square. There was a faint click and then the square block rotated, pulling away from the wall before drifting downwards, seeming to float by itself with no means of support, as rock-solid as if it had been sitting on some actual surface. A moment later, the upper surface lit with a complicated series of screens and gridded symbols. Aislynn paid as much attention to her sonic as to the new buttons, looking back and forth between one and the other.
"Is there a point when you've seen so many wonders that your mind just starts to accept them as commonplace?" Watson asked Diana softly.
"No, not really," she replied in an equally soft tone. "You get used to some things, sure, but not all of it." They exchanged small smiles and then turned to focus on Aislynn again.
"Mind you, mechanica is really Taydin's forte, not mine," she explained, "And Aedok is difficult to translate at best. However, if I have this worked out correctly…" The buttons slid around, rather than remaining in one place, to interlock like puzzle pieces, and she spent a few minutes moving a few of them into a new configuration.
The tunnel lit up.
There, some four yards in front of them, was a solid wall. It was glowing and transparent, and appeared to be made up of cubes of energy. It's color was a deep gold; there were points where a number of squares were turning orange, or even deepening into a reddish shade.
The tunnel continued on the other side of the wall, the identical size, shape, and direction. The London tunnel was all soot and bricks and piping. Beyond the wall, its other half was made of lightning. There was nothing to show why the lightning should pack itself into nearly-solid surfaces, but it had, forming a round tunnel leading off into blackness. Lightning was jumping from one side to the other, spitting and sparking, but it appeared to be quite stable. It reminded Aislynn of the Vortex.
She squinted, as the picture on the other side of the wall seemed odd. It was out of focus somehow, or fuzzy, as if it was part of a badly-tuned television image.
Both Aislynn and Holmes stepped forwards at the same time to examine it more closely.
Aislynn blinked in surprise as she realized that other side of the wall wasn't out of focus. It was obstructed in places by darting angles and flickers of unlight. The Yr were there and in large numbers.
Holmes scowled ferociously at the sight.
"I suspected there might be more, but I was hoping it wouldn't be so many. There must be dozens, the train..." He trailed off abruptly as he and Aislynn exchanged a significant glance at each other. It seemed to her that they had each come to the same conclusion at the same time.
It was Holmes that was fastest off the mark, dashing back the way they had come, with a sudden burst of speed. Aislynn smacked the maintenance panel shut and was off like a shot after him, as the panel closed up again in her wake, plunging the tunnel into sudden darkness as the lightning vanished, and their surroundings were once again all bricks, soot, and pipes.
By the time that Watson said, "Wait, what?" the humans were already by themselves in the darkness.
"Do Time Lords do this to you often?" John turned and asked the others, and they all nodded their heads.
"All the time," said Owen, following in Watson's wake as he began chasing Holmes and Aislynn down the tunnel. "What about Holmes?"
"Constantly," Watson shot back over his shoulder.
"Why are we running?" Katie cried out and John didn't have the breath to answer.
"I have no idea!" Diana replied and he almost laughed, realizing that none of them had a clue as to what was happening.
By the time that they had reached the train, Holmes and Aislynn were already both long gone.
Taydin was peering from the train as they ran up, a perplexed look on his face.
"What's going on?" he asked them.
"Oh, nothing!" Owen snarked back. "Just random running!" A sentiment that Watson heartily agreed with.
They finally caught up with the other two in the second tunnel, where Aislynn was already folding down the maintenance panel for the new tunnel. As before, she brought up the wall, but this one was less gold than the first: it was more orange, and several of its squares were turning red. John didn't know what any of it meant, but he strongly suspected that red was not a good thing at all. At least he could deduce that by the matching expressions of unhappiness on both of their faces.
"More of them," Holmes spat and then darted back in the other direction, with Aislynn only a step behind him.
"Holmes, what the blazes!" protested Watson, windmilling his arms, as Holmes all but ran over him. Owen, Katie, Jake, and Diana, scattered as Aislynn shot between them.
"Come on, John!" Holmes called back over his shoulder. Watson grumbled under his breath but turned to follow.
"You're missing the middle bits again!" Diana called to Aislynn as she took Jake's hand and darted after her. "We just talked about this!"
Owen and Katie looked at each other in exasperation. Owen took Katie's hand with a feeling that they were missing out on a lot of information and they ran together.
"I will say this," Katie joked to Owen. "All this running is good for the figure… I think I may have lost five pounds."
"I'm not convinced," Owen smirked, even though he was now panting a bit from exertion. "I'd have to give you a much closer examination to be sure." He kept his voice low so as not to be overheard by the others.
"Behave!" Katie giggled.
They finally reached the third tunnel, Watson panting and blowing at this point. Once Aislynn had activated whatever she was activating, it looked identical to the others. It was the same deep orange, and with flickers of Yr rushing about on the other side. This time they all flattened themselves against the walls as the Time Lord and the detective plowed through them headed off again.
"Middle bits!" Called Diana again at Aislynn's heels. Watson didn't even bother to shout, he was far too winded.
"Don't worry, Angel," Jake grinned at her as he took her hand and they again gave chase. "This is the last tunnel."
"Just once I'd like to get some answers before the last tunnel," Owen told the rest of them.
"That might take different Time Lords than the ones we have," Katie grinned at him.
They caught up just as Aislynn was activating the last panel.
"Holmes, what are these - " Watson started, bent over, breathing heavily, and now getting seriously annoyed.
The tunnel lit with an eerie red glow and Watson's aggravation vanished.
"What the devil!"
This was from Holmes. Aislynn drew a breath so sharp that Watson spun to look at her. Even in the deep red light, it was clear that she had turned as white as a sheet.
This glowing wall was a deep crimson red all across it. At first, it looked to Watson as if the tunnel didn't continue on the other side. It seemed to stop abruptly and there hardly seemed to be a flicker of lightning to be seen through the red.
Staring at the crimson walls, it took a moment for him to grasp why the tunnel seemed to stop. He realized that the other side of the wall was completely obstructed by the Yr, Yr in countless swarms.
Holmes voice was low.
"There must be thousands. Hundreds of thousands."
Katie looked down abruptly, then reached into the pocket of her nurse's apron. From it she drew the clock that John had examined earlier. The alarm was not going off, but it was making a deep buzzing noise.
"Aislynn!" Katie held the clock out and Aislynn tore her eyes away from the red wall in order to look at it. "The alarm isn't going off," she remarked, but her voice was uncertain and Aislynn just shook her head.
"Not yet," she replied, her hands twisting together in anxiety. "I need to talk to Taydin!" As before, she closed the maintenance tunnel and then bolted back towards the train.
"Holmes, what does this mean?" John asked, frustrated with the lack of explanations.
"I'm going to find out," Holmes answered and then he was off again.
Diana and Jake quickly outdistanced him, though he was mollified by the fact that Katie and Owen were behind him. He emerged from the tunnel just in time to see Taydin step from the train, and Aislynn run up to him. The tunnels had not been kind to the lovely striped walking-suit. She had soot on her shoulders, along the sleeves and smeared on the skirt, and the hem was muddy for six inches from the hem. Not that any of them looked much better, he noted ruefully.
"We've got a problem," Taydin and Aislynn said to each other at the same moment.
"You first," said Taydin grimly.
Aislynn nodded her head, still breathless from the run.
"The entire system is orange-shifted," she said with a gasp for air. "The exterior shielding has already fallen and Beta quadrant is full crimson; it's not going to last another year. I'll be surprised if it lasts the season."
"Madame," Holmes said impatiently, "Further explanation is required."
"The tunnels are coated in those damnable things!" John added, hoping that he was adding something of use, since Aislynn seemed to have forgotten all about them.
Aislynn looked abruptly guilty as she saw the faces of the rest of the group.
"Oh… yes, of course… I do apologize, to all of you. I just…"
"...got distracted and forgot we didn't have all the middle bits?" Diana prompted, but her voice was teasing. Even so, Aislynn's cheeks turned pink from the chastisement.
"I am afraid so. I do beg your pardon, all of you."
"A simple clarification of the facts is all that is required," Holmes insisted, foot tapping..
"Yes, of course," Aislynn quickly agreed. "London is a hub for this transportation system." She gestured at the empty train. "As such, this area has been set up with protection. There is a shielding system that acts to filter out contaminants, or as protection against hostile foreign entities. The system has been abandoned for millennia, but when it was built, it was set up with mechanisms meant to be used for maintenance. The panels that you saw in each tunnel were maintenance panels meant to run system diagnostics. These particular diagnostics are heavily based upon photon induction…"
"I bet I am not the only one here who is not familiar with photon induction," Diana interrupted, her hand held up to forestall a long explanation that Watson suspected would be completely mystifying anyway.
"Ah, point. They are… hm… color-coded, across the spectrum of visible light. You are familiar with the way that a prism will split light into its component colors? These diagnostics work in much the same way. A shield functioning at peak efficiency would be lit in a brilliant violet color; as problems are encountered, the color downshifts to reflect reduced capacity. A single square appearing in any color of yellow or below is a square with a problem; to have the entire system reflected in orange indicates that the shielding is in deep distress."
"And the red wall in the northeast tunnel?" prompted Holmes.
"On the verge of collapse," Aislynn said and turned to Taydin. "We've got to find a way to give it more power, or enhance its effectiveness, somehow."
"That might be tricky." Taydin grimaced, but turned and looked at the train. "We might be able to pull a bit of power from the battery car," he mused. "We can reroute the tachyon flow and divert part of the shielding on the stairs: we don't need seven feet of psychic shielding, three would do."
"We'd never get the power to reverse the damage…" Aislynn protested.
"No, but we could stabilize it for a while. Give us time to figure out what to do long-term."
"Long-term, we've got to get rid of them," Holmes snapped.
"Yes, the question is how, if one managed to slip past the shields then… wait, how did that one slip past the shields?" Aislynn looked at Taydin as if expecting him to produce an answer out of thin air.
"Is there already a hole in the shield?" Owen asked, but Taydin shook his head.
"No, it's not structured that way, it can't support holes… it's an all-on or all-off sort of setup. Either it keeps them all out, or lets them all in. There is no in between."
"So… how did the first one get into London?" wondered Katie.
"There are several possibilities, but we'd have to catch it to find out for sure and London is a city of millions of people, I don't know how we would ever be able to find…"
His voice trailed off. As one, he, Aislynn, Katie, Owen, Jake, and Diana all looked at Sherlock Holmes.