Disclaimer: "Harry Potter", "Crest of the Stars", and "Nadia: The Secret of Blue Water" belong to their respective owners. This disclaimer will apply to all future chapters, unless noted otherwise. (It also applies to the previous where elements of Nadia are mentioned. You can consider the Nadia universe to be an AU. Changes have been made to make everything fit.)

Severus could scarcely believe the pile of stuff packed into the room of requirement. No boxes. It was all in big cloth bags, which is how they were bringing in the cloth to make new suits and clothes. The only gap was the outline where he knew the crystal caskets were positioned in the real Atlantis.

For notebooks he had ended up traveling to a muggle bookstore and purchasing acid free laboratory note books each with 100 pages. They could easily be combined with charms and the paper was very high quality, and more importantly weighed less than the equivalent from a magical bookstore. A whole bag full of the pens that had become popular after that group introduced them were also included.

The food was a mistake. He knew it was a mistake. He sighed as he looked at the bags of muggle can food she had found. It required no magic, and it stored a lot of food, but he couldn't help but sneer at it. Perhaps this was punishment for raiding her potions stores. Then there was the muggle oatmeal. Disgusting. He was really beginning to regret his idea. There was no fresh food at all. He had pointed out that he was very accomplished at preservation charms. She pointed out that they were still somewhat limited, and if they got stuck there for a very long period of time the preservation charms would further reduce the quality of the duplicated food. Stupid healers and their logic.

Sadly, meat was also pretty pathetic. Tuna fish and sardines. Neither required chilling charms. Even here, Poppy was preparing we if they had to magically duplicate the food for years. He appreciated the forethought, but tuna and sardines were disgusting.

Still, they were ready. Daphne looked about ready to rebel when she saw the food. Samantha was no better. She looked at their food, turned around and left. They were still waiting for her to return.

When she returned she had another cloth bag that she refused to open, saying only that it was essential supplies. Severus hoped it was something good. He knew they were close to how much this would be able to carry, but they had done the math. If they failed, they should be tossed out somewhere in the air, and would have seconds to line of site apparate to the ground. They also knew enough to figure out their location magically and to multi hop apparate to any number of places where they could rest and recover. Severus had tested Daphne's ability to apparate in stressful conditions. They were ready.

Severus nudged the bag. It was something solid.

He glanced over to the last remaining clear spot on the floor where Samantha was waiting on a reply from the real Atlantis. He saw it being written.

Samantha said, "They are ready. We are going in thirty seconds. Last chance to get off."

No one moved. Severus tried to nudge the bag open, but Samantha swatted his hand away.

He restrained his curiosity as the seconds wore away and suddenly they were on the portkey trip from hell.

He immediately tried to find something to hold onto, only to have to grab hold of Samantha as she did the same. They managed to remain standing.

Daphne didn't and ended up falling and banging herself against the crystal wall at their destination.

Severus immediately recovered and cast a diagnostic spell on her. He said, "Your fine. Hold still, I can fix you up."

She glared at him, even as she felt him healing her bruised elbows and rear end.

He said softly, "You do know that your different now?"

She nodded. Samantha looked on in curiosity, but said nothing.

Luna was the first to pop in. She immediately went to Samantha's bag, pulled out a dark chocolate bar and started nibbling.

Severus smiled and held out his hand for a piece. Luna reverently broke off a tiny piece and handed it to him. He kept his hand out till she handed him a larger piece. He mused that duplicated chocolate might even be healthier. Probably not, but it sounded good.

He said dryly, "We should have brought some actual meat, but at least we have chocolate."

Samantha said, "I hid some beef jerky in the bottom. There is enough to duplicate. Had I known how bad it was going to be I'd have prepared better."

Severus nodded. It was something.

Luna picked up Samantha's bag and carried it out, which was apparently accomplished by just touching an empty section of the wall.

They soon emptied the room and stored all the food into nearby rooms.

Lafiel directed them to a nearby conference room she had found. The conference room chairs were metal and completely lacking cloth, but that could have simply been the passage of time. Thankfully the cushion charms he felt when sitting down made them irrelevant.

The table was round and more crystal, as if it had been grown from a single solid chunk of crystal. Amazing.

Lafiel was the first to speak, "Why did you come? This could all end badly."

Daphne replied, "We all knew, well not the exact odds, but we knew the risks and thought we might be able to help."

Lafiel nodded. She went on to explain their plan, alternating with everyone until they were done.

"You have been busy," Severus commented. "You do realize that you charging up this artifact is not likely to go over well. I'm no expert on this, but..."

"But I am," added Samantha. "What your doing is violating several laws that I know you don't know, but not energizing ancient runic arrays to see what happens is definitely pretty well up there. These are the kind of laws where the ICW collects you without warning, giving you a nice secret trial before you are never seen again. The ICW ignores a lot, except what they don't. Things that are a serious legitimate risk to multiple countries are in that category."

Hermione looked worried. They all did, though Fleur's expression was particularly grim.

Victor shrugged. "Laws not mean much if we are dead."

Samantha sighed. "Your plan may be the best one, though the fact that you hid many of the details indicates you knew part of what you were getting into. You said you talked to Nadia?"

Luna said, "Quite often. She is our friend. You just need to place your hand over the crystal."

Lafiel added, "You can only talk to her once a day, but I don't think anyone has yet." She looked at the others to and got nods of agreement.

Severus said, "I'm a pretty good judge of character. Let me. Maybe I can spot something."

Samantha nodded. They returned to the chamber and Severus carefully rested his hand on top of the casket above the shinning blue gem. "Nothing is happening."

Luna said, "You have to use a bit of magic and want to talk to her."

Severus vanished.

Severus appeared in a great field of grass, but something was wrong. His arm was burning. He smelled smoke.

Nadia looked at him in anger. "You bring such corruption into this place."

"Stop," he begged.

"No, I will not. You will have to endure it, as I sense you have for a long time."

"Fine," he gasped, even as he employed all he knew about occlumency to resist the temptation to cut his arm off with a spell.

The burning went on for seconds, then minutes. He thought it was close to fifteen when the burning stopped. The pain was still enormous. It was only his skill with Occlumency that was keeping on top of it.

She said, "It is done. The residue in your arm has been purified."

Severus tried to move his arm, but it wasn't responding.

"I can help you heal before you leave, but for now, let the magic disperse. Your own magic should be able to do some of what is needed."

Severus nodded. He said, "Samantha and I do not trust you."

"I know. What I did probably didn't help, but you are inside the blue water when you are here, and I have a duty to defend it against all corruption, even if it kills me. I would kill you in a heartbeat, if it was necessary to prevent its corruption."

"How do you know my arm can be healed?"

"I am honestly not certain it can. I will try. The blue water has taught me much, and with time I could have done that more carefully, but I was not given the time or warning. Please explain how you came to posses such dark magic as part of your body."

"I've made mistakes. There really isn't much else to say. The one behind that mark is dead. The pain you gave and even if it costs me an arm are not remotely enough to pay for all my mistakes, but I am here to help."

"I know. I could sense that much. I would not have pulled you in had I not. Unfortunately, I did not sense the darkness until it was too late."

"Convince me that letting this charging of that artifact continue is a good idea."

Nadia laughed. It was a bitter laugh in a voice he thought would be better if it was not so sad. "You ask me to convince you of something I think is probably wrong? My advice remains unchanged. Take Captain Nemo with you to the ship. I can hold and protect you long enough. I have enough power to force the wards to fail. I will do my best to make sure you get out."

"You would have us abandon you?"

"It may be better than setting the legacy of Atlantis free. So very many people have died for this, but then there are other concerns."

"What concerns?" asked Severus.

"You don't know, do you? They have nothing to do with me."

"What are you talking about?" he asked.

"If you don't know, I can't tell you. Know this though. The blue water has taught me much. If we are free I can control it well enough. The true risk would be if I were to lose it, particularly if I died and the binding to me vanished. It would weaken the blue water, but in the wrong hands, it could still cause countless damage. I was locked here with my friend to both preserve this place and to weaken the protections on the crystal. That they never came back was a blessing. Hopefully they are dead."

"Who?" asked Severus.

"The other survivors of the Atlantian race. I presume they didn't make it, or you would know by now. Not all of us were as nice as me. My people came to your world. We modified primates, creating you in our image to be servants, but then you rebelled. Nemoy and I helped that rebellion so very long ago, and here we are, trapped in time. Fawkes got free at some point. I'm not sure when. There is a lot of irony in my story, but then I suppose you wouldn't understand that yet. Perhaps you will soon."

"Can you explain at all?"

"Unfortunately not. The secrets I speak around are not mine."

"Lafiel then. What it is with blue haired people this year?" he muttered darkly.

"Lafiel is not an Atlantian, though her hair color does amuse me."

"Then what is she, and what did her becoming Daphne's relation change?"

Nadia walked up to him and placed her hands around where the mark was on his arm. Warmth flooded him. His whole arm began to itch and then, less than a minute later it receded.

She smiled as she ran her hands over it. The glow faded as she withdrew her hands. She said nothing else as she turned and walked away. Severus soon found himself back in the crystal chamber leaning over her casket.

He quickly flexed his arm, checking it for motion, before he caught Lafiel looking towards him from a few feet away. "She left me many questions about you. Why are you different?"

Lafiel turned to look at Daphne who gave her a small nod. She then looked to Samantha before turning back to Severus.

She said, "I'm from almost a thousand years into the future. My people were designed and built by humans to use as slaves. We rebelled, needlessly killing many of our original masters. In time we developed a civilization. I am third in line to the Imperial throne. I believe the Empire is overall good. We are hardly perfect, but we try to just let people live in peace. Some resent us because we deny them arbitrary power to travel in space and access to our faster than light technology which allows us to move between worlds. Do not misunderstand. We do not stop space travel or commerce. We regulate it. Our goal is to protect the planets sworn to us and prevent needless conflict."

"I was sent here by mistake, when an experiment in a new form of faster than light travel that somehow involved magic shot me back into the past. I detected similar emissions from your world, and then eventually homed in on the wards protecting Harry here as a nice out of the way spot that might help me figure out how to return home."

"Of course," Severus said dryly. "It had to involve Harry Potter."

Daphne laughed. She said, "Your less annoyed that it apparently involves time travel and created people than that it involves Harry Potter."

"Your point?" he asked, confused.

Daphne laughed some more. Harry remained very quiet even as the others were stunned.

Annoyed, Samantha said, "Moving on from that bit of insanity that I'm pretty sure Garnok knew about… Your opinion Severus. Can Nadia be trusted?"

"I detected no reason to not believe her. I assume one of her other comments were possibly related to Lafiel and a desire for her to get home. She is worried that our plan is a bad idea. She did, however support another plan which gets the other guy here out and where she dies saving us. I think she was serious in saying she would support that plan, but I also think she doesn't want to die."

Lafiel said, "We do plan to use their submarine in any event, and not just to get out. It is not a spaceship, but it might be possible to convert it into one. The metal is at least a strong enough foundation to start with, which is more than I had."

"What about your own ship or whatever?"

"It is too small, and the special engines that launched me on this trip were actually installed on a much larger ship. It was the only way we could make it work."

Samantha said, "So, you left on a trip with something highly experimental, that you didn't fully understand without even the resources to repeat the trip?"

Lafiel said, "To be fair, the engineers all agreed one hundred percent on the risk from the trip."

"And that was," Severus asked dryly.

"They told me flat out it was far too risky and not to go. The Queen said she thought the technology was too important, so I went. In hindsight I think she may have had something from this time. A pensive is my guess."

Samantha asked, "So your saying your part of some stable loop of time?"

Lafiel said, "That is my guess. I don't actually know."

"Lovely, well chalk up a few more violations of international law."

"No?" Lafiel said sheepishly. "Besides, it is not as if I have a clue how to return. I'm just doing what I can within imperial law."

"Of course," Severus said dryly. "Having your own system of laws simplifies things."

"Not really."

Daphne answered, "She can't introduce technology beyond a certain level here without violating her own laws, not to mention being unsure if she even should."

Severus said, "I really should have quit after the Dark lord and his followers went through the veil." He turned to Harry. "Tell me you plan to go with her when she gets all this going?"

"Uh? Maybe?"

"Oh happy day."

Daphne burst out laughing again.

Two days later, after both Samantha and Daphne talked with Nadia, they agreed to continue the plan as is. The Atlantian seeds they found they decided not to try to grow, though they did retrieve the crystals they were kept in. They would be given to the ICW after the appropriate negotiations. Their days were other wise filled with detailed drawings, maps, and descriptions of this place. It was, Severus thought, a much more interesting life than teaching a bunch of ungrateful brats.

Their vegetable garden ended up being hydroponic with a fair share of magic involved since they had no dirt to work with, and while the idea of using their own waste was at least mentioned by Hermione, it was swiftly canned. After a bit of trial and error Victor and Fleur were maintaining it the garden. Magic could accelerate plant growth, but you had to be careful not to add too much or you ran into the same problem as copied food. It was three weeks after their arrival that the first tomatoes became available. They became a fast favorite. Seeds from them were quickly used to add even more tomato plants to their impromptu garden.

The chocolate was replicated almost right away, so as not to risk running out. It wasn't healthy, but no one really cared.

Their biggest problem was the Nautilus. The engine core for the submarine was missing, nor was it anywhere else in Atlantis, as several spells combined with a detailed search confirmed.

Unfortunately no records existed, not even in the Blue Water of how to build the Nautilus's fusion engine. The Blue Water had some general fusion designs, but there was nothing there they actually had the material and know how to build. Well, that wasn't entirely true, there was one potential design, but it lacked the ability to produce the kind of power they would need to escape. The Nautilus's engine was relatively new at the time they were imprisoned. It was one of a kind. It had to be to provide all the energy that ship needed to operate.

Lafiel checked her tablet as well, but without access to a link to her ship, she had even less to go on. She might have been able to copy a fusion engine design if there was one in there. They were less restricted than antimatter based designs, but they would still lack the necessary infrastructure to build it or adapt it to the Nautilus.

That left them with their own design for a super heated steam engine based on magic, but they couldn't figure out how to build one that would actually survive the energies involved, let alone handle them safely. Fortunately, Nadia had an answer. She directed them to a crystal workshop with still raw crystals, a dozen of which were what Nadia classed as perfect and of immense value.

It took the whole Arithmancy team to figure out how to pattern one and grow it with magic to the shape they needed for the engine. An additional five of the last dozen perfect crystals were used to create control rods of a sort for their magical reaction, with each member of team blue responsible for magically inserting or removing a rod from the system to control the reaction rate and how fast magical energy was drawn from them.

When they first lit the engine, Severus had made the mistake of being in the room with Team Blue. It was not a mistake he intended to make again. That much controlled magic was just wrong, on every level.

The math may say it was necessary, but it scared the crap out of him. The fact that Samantha's own notes mentioned that if it failed it had the potential to create a class one magical disaster area didn't help.

To make matters worse, they were not completely sure the engine could handle their power requirements. The notes suggested it would be close. It was mostly the size it was, because that is as big as they could create with what they had.

The idea that its purpose was merely to super heat some special fluid which itself was used to turn other generators just seemed insane to him. The fact that any leak of this super heated special fluid would be nearly instantly lethal if someone got in the way did in no way reduce his concern. Nadia assured him it was as safe as they could make it.. He didn't feel particularly safe.

One good thing was it turned out to only to take one person to keep the ship systems active power wise, but that was when they were sitting still. Getting out was going to take a lot more.

Fortunately the addition of power allowed Lafiel and the others to begin to puzzle out many of the ships systems, but they readily admitted that they were guessing, and had no desire to effectively take the ship into a hazardous situation without someone who knew what they were doing.

Their other challenges seemed nothing compared to the demon room, as he had come to think of it. Somehow he was sure they only went to five because they were five in number. He shuddered to think how bad it might get if the demon engine had a full set of seven people behind it.

ted finally settling on, "If you can activate the systems with less than half of one persons magic, then I would think two would be adequate for getting out, but if things go badly, and you need the weapons systems to escape, then yes, all five at full power or maybe more may be required."

Language was also a challenge. The blue water crystal provided a cheat allowing Nadia to understand them and communicate with them right away. Captain Nemo would not have that benefit. Daphne and to a lesser extent Lafiel had taken up much of Nadia's time as she patiently taught them her language.

It wasn't limited to Daphne and Lafiel though. Everyone was trying to learn it from them, so as to have a better chance of operating the ship. Luna was the strangest of the lot, since while she didn't take of Nadia's time, she seemed to be learning the languages the fastest of all, with only the secondary lessons. The girl could be caught at all hours of the day sitting between the caskets and simply describing her day, or something she remembered, or a magical animal or anything. It was quite remarkable.

Hermione had taken to spending part of her time there, simply listening and trying to follow. It was clear that the Ravenclaw had a true affinity for languages, just not in the teaching of them. He still couldn't believe the girl had successfully grown radishes from her earrings. He was sorely tempted to step up the difficultly of the girl's potions lessons just to see how she would do, but he was reasonably certain whatever the result was, it would give him a headache.

His biggest challenge was a side project to produce alcohol. It was for medical purposes of course. So far, that was a dud. They lacked the right materials, and his suggestion to use one of the remaining perfect crystals to grow a still was promptly rejected, though Samantha looked like she wanted to support it. People had tried to magically create stills in the past but it always ruined the work and the potions equipment he had wasn't adequate to the task. He had managed to produce small amounts, but nothing palatable.

Their remaining challenge was surprisingly needlework. The elves that did their other flight suits weren't here and they had to do the work themselves. Fleur and himself turned out to be the best at the needlework. They practiced with conjured cloth and thread, rather than waste their limited supplies. His eye for detail helped, and Fleur was just good at it. It took over a month of practice before Samantha considered their work to be high enough quality to risk on a flight suit. A week later they Severus had a suit.

He was amazed as he slowly rose above the submarine. He was more amazed when Daphne at his request fed just enough magic into their planned exit array to light it up. He shuddered, and almost lost control of his suit. All that just to melt, well a lot of ice. He didn't know what scared him more, being in the metal contraption or the metal contraption being inside that bit of a warders nightmare.

He focused on his own occlumency to regain his calm. This was almost worst that the demon room. They obviously didn't really summon demons there. He just thought summoning demons would be a less dangerous task. Perhaps he could suggest something else for Potter to do? It would surely be safer with one less Potter.

He reminded himself once again this was their best plan, and in fact their only plan, that the only variable they really had was whether to let the girl die and take her troublesome gem with her. No one wanted that. It was a pity they couldn't leave the gem behind somehow, but that too was impossible. It had kept her alive too long. She was dead without it. And with his luck, the girl was right and they might need it to get out alive. The fact that she had mentioned using it in the same room as those five seeds of trouble.

Nope, he was not going to think about it. He was going to think of the nice potion he was going to brew to make himself forget all about all the ICW laws they were breaking, and the likelihood they had of spending a lot of time in, well not Azkaban, that was a British thing. Just where did the ICW dump their criminals? You'd think he would recall that. That brought another disturbing thought. You never heard of an ICW criminal being released.

This muggle submarine thing looked very troublesome too, and that was excluding the demon drive. He knew little about them, but Hermione had told them that only powerful muggle governments used them, and that the technology in this one could easily start world war three. Apparently it could move a lot faster than anything else in the water, and had weapons systems that could easily destroy lesser submarines. Severus once again cursed the name of Potter. The only good thing is that it wasn't currently fully armed, and at least didn't have the muggle nuclear weapons.

Perhaps the girl and the captain could just keep this thing out of sight when they got out? That was their plan at least.

It was one week out from their expected go date. They had filled all of the books they had brought with detailed notes, drawings, and even some very realistic pictures as drawn by Luna. Lafiel had filmed over a hundred hours of detailed video with her tablet, which was apparently close to its available capacity without a link to her ship or being willing to delete data from it.

Nadia's blue water crystal was fully recovered to its ideal state, with all of its protections intact. She now had the power to collapse the wards at any time. She again offered to sacrifice herself to guarantee their escape with Captain Nemo, and they again refused it. Severus personally thought she worried more about the jewel. She needed it to live, but it was also dangerous. What must it be like to see the pinnacle achievement of a civilization and only wish it destroyed, but to rely on it to live; to fear that people would die again to try to posses it.

They figured out that the wizarding world, and in fact all the magicals and creatures in it, were descendants of the peoples of Atlantis, of the people that imprisoned Nadia here. The exact details were unknown, but they were what became of such a great people that could travel the stars as easy as they traveled across the street.

Some would say it was the muggles and breeding with them that led them to their sorry fate. Severus didn't buy it. They had somehow been giants. They had created the muggles, and then tried to use them as little more than slaves.

How many times did the cycle of misery have to repeat? He slammed his hand against the table in his bedroom as he contemplated the tragedy of it all.

He had also spent time with Fawkes. Or rather talked, and watch the bird shake his head in either agreement or denial. Fawkes wanted to save Nadia most of all, but if things went to heck would simply save who he could. That was fine. He told the bird to come for him last. It probably wouldn't be enough to erase the debt on his soul, but it was the least he could do.

The bird didn't like the demon room either. He had asked Samantha about it once and she shrugged at his question. He stated that he actually wanted her honest opinion. She turned to him and said soberly, "No. Actually you do not."

Then she got closer to him, so that her slightly shorter form was staring at his face. He actually moved back a step from the rather intimidating older woman. She said, "I'm not sure we are getting out of here alive, but don't tell anyone and I mean anyone about what we built. The energy that thing can control is insane and do you know something else?"

He moistened his lips. "What?" he asked.

"It's nearly lossless. Just one person could, over time, build up enough power to blow Hogwarts off the map, and no I'm not kidding."

"Do they..?"

"Of course they know. Don't be stupid. They." She paused then said more loudly, "We invented the Arithmancy for it. That we found a super material here that increases the potential at least an order of magnitude beyond what we thought possible just makes it worse."

"And all of this is really needed for that ship thing?"

"For us to get out alive. Yes, we need it. Two should sustain normal operation. Maybe one if we are careful. Five plus Nadia is the north pole collapsing on us territory, which guess what, it might!"

"Damn Potter," he cursed.

Samantha said, "He is not at fault you know? If anything it is Fawkes. He is the only one that apparently knew things in time to stop it."

He said dryly, "I didn't complain about your chocolate addiction."

She laughed.

He said, "I've done some very unwise things for a girl before. Needless to say, I have no right to criticize Fawkes."

She nodded soberly, evidently knowing his true history.

It didn't matter. It was time to awaken the captain and get this show on the road. The time for dithering was over.