"Are you going to tell me what we're doing?"

Harry grinned mischievously at Aria, practically skipping down the corridor carrying a beach towel and the Golden Egg. Aria glanced at their Slytherin dormmates who also looked as confused as she did.

It was the new year. Students had arrived back at Hogwarts for the new term yesterday, but as they had arrived back on a Saturday, today had been a day of taking in the indulgence of hanging out with friends before the school year started. Harry had hurried about all day inviting people to some kind of get together that he was super tight lipped about.

They stopped on the fifth floor, four door down from the statue of Boris the Bewildered. Harry boldly stated a password and opened the door, waving the 4th year Slytherins in.

"The prefects' bathroom!" Blaise breathed as everyone filed into the large bathroom. "Look at that tub!"

The "tub" was less of a bathing tub and more like a swimming pool. Around the edge of the large room were doors leading to private shower stalls. Above the tub was a stained-glass window showing a mermaid combing her hair.

"Cedric gave me the password," Harry explained as he stripped down to his bathing shorts. Aria was treated to the gasps of their housemates as they, except for Draco, had never seen a Muggle styled bathing suit before. "Told me to "take a bath" and then gave me the password and directions to the bathroom. I thought a bit of a swimming party might do us some good."

The door opened revealing their Gryffindor year mates except for Fay and Sophie.

"What're you wearing Harry?" Lavender cried seeing Harry's bare chest. The other Slytherin boys began chucking off their robes, revealing their bathing suits more suitable to the 1800s with long shorts and a matching short-sleeved top of tank top.

"A bathing suit," Harry answered, fiddling with the many spouts. Water and bubbles appeared. "What kind of scent do we want?" The smell of jasmine and rose filled the rapidly steamy bathroom.

Dean also had Muggle swim trunks and Seamus, seeing that Harry and Dean weren't shy being bare chested, immediately removed the short-sleeved shirt from his own wizarding swim wear. The three of them jumped into the tub. Ron and Neville did not remove their shirts.

Aria and Hermione revealed their own swimsuits. Hermione's was, surprisingly, a dark blue tankini with golden flowers blossoming over the belly area while Aria had decided to wear her favorite one piece which was white with floral designs on it.

"I can't believe Muggles swim in those," Parvati said as she and Lavender revealed their cute witches swimwear. Both consisted of a short sleeved top that looked like a mini-dress and matching bloomer pants that fell to their knees. Lavender's was, of course, pink and white while Parvati's was yellow and blue. Daphne, Pansy, Tracey, and Millicent revealed their own swimsuits, very similar to Lavender and Parvati's, though sometimes the style of the sleeve and the cut of the top dress was different. Daphne's top dress was a soft baby-blue and her bloomer pants a dark navy while Tracey's was all navy except for silver accent striped around the hemlines and neckline. Pansy's entire top dress had polka-dots while her bloomers were a solid red. Millicent had stripes up and down her top dress in orange and gold while her bloomers were orange.

The door opened again and the Hufflepuffs arrived. Susan, Hannah, Ernie, and Justin greeted everyone warmly and they went through the standard round of shock at seeing Justin's Muggle swim trunks and Aria and Hermione's Muggle swimsuits.

After the Hufflepuffs came the Ravenclaws showed up. Aria knew Harry did not talk a lot with Ravenclaws, but that at the Yule Ball, he had gotten friendlier with a few because he had taken Luna and Ron had taken Padma. Padma, Lisa Turpin, Anthony Goldstein, Terry Boot, and Michael Corner were quick to join them in the tub. Lisa nearly had their classmates in pieces when she revealed her cute bikini, which Aria thought was quite tasteful for a bikini. Her bottoms were a skirt, and her top was really more a crop top, only going as high as the top of her belly button, before the straps widened to cover most of her shoulders.

The fourth years splashed around. Several water fights ensued and someone conjured up a beach ball in the colors of the Hogwarts Houses.

Eventually, though, once they were all exceptionally pruney, Harry picked up the Golden Egg.

"Cedric didn't tell me what the egg said," he told them as they all grimaced at the idea of opening the object. "But Cedric said that I needed to open it underwater. I don't know where he got that idea from."

"Probably he chucked it in the tub," Susan said. "We banned him from the common room whenever he opened it."

Harry put the egg under the water and opened it. No shrieking was heard, but everyone could hear some kind of noise, almost like muffled singing. Taking deep breaths, the 4th years slid under the water. Those capable of opening their eyes underwater saw that the normally hollow egg gave off a glow of light shaped like the egg. They all could hear the melodious singing coming from the object now.

"Come seek us where our voices sound,
We cannot sing above the ground,
And while you're searching ponder this;
We've taken what you'll sorely miss,
An hour long you'll have to look,
And to recover what we took,
But past an hour, the prospect's black,
Too late, it's gone, it won't come back."

Aria gasped for breath as she came out of the water. Her friends all took a few minutes to catch their breath. The song was not long, but the singing was not fast, and they could all feel the burning in their lungs from staying underwater.

A giggle overheard alerted them to another visitor. Moaning Myrtle floated above the tub.

"Listening to music in the tub?" she questioned with a slight giggle. "The other boy did that too."

"Cedric?" Susan asked.

"I don't know his name. The pretty one."

"Definitely Cedric," Anthony muttered.

"But what could the song mean?" Ernie asked. "It makes no sense!"

"Let's take it one piece at a time," Hermione suggested. "The first portion was 'Come seek us where our voices sound, we cannot sing above the ground'. Who is the 'us'?"

"Probably whoever sounds like a banshee when not in the water," Ron said. "I don't recall learning about any creatures like that in Care of Magical Creatures."

Lisa tsked, pulling everyone's attention to her.

"I think it's describing mermaids," she told them. "I've been obsessed with them ever since I first say The Little Mermaid as a kid. When I learned I was a witch, I immediately went to see if they are real. They are. They speak a language called Mermish."

"Does it sound like a banshee?" Dean asked. Lisa shrugged.

"I don't remember off the top of my head," she said.

"But where are their mermaids at Hogwarts?" Tracey asked.

"Myrtle," Aria called to the floating ghost who was looking at the mermaid in the stained glass and combing one of her pigtails with her ghostly fingers. "Are there mermaids in the Black Lake?"

"Of course, there are," Myrtle answered. "I did one of my Care of Magical Creatures essays on them. I was going to be a magizoologist before I died." She sniffed. Aria was struck with how different Myrtle was as a ghost than as the girl in her vision.

"Okay, so I'm probably dealing with mermaids," Harry said. "What else?"

"Well, the song makes it sound like they're going to take something that you like," Neville mused. "And you'll have an hour to find it."

"So, I've got to swimming?" Harry questioned.

"In February?" Michael cried.

"I can't swim in the Black Lake!" Harry insisted. "I've never swum in anything deeper than a 9-foot pool!"

"And how are you supposed to swim underwater for an hour?" Terry questioned. That stumped everyone.

"Scuba gear wouldn't work would it?" Dean questioned.

"It might," Hermione said, "it's not running on anything that dislikes magic like electricity. The question would be how to get it here and how to use it. I've no idea how to scuba dive do you?"

"What's scuba diving?" Draco asked.

"It's how Muggles swim underwater for extended periods of time," Hermione explained. "They strap a tank full of oxygen, that's what we breath, to their back and use a nozzle in their mouth to breath in the oxygen while they're underwater."

"So, we need to find something similar to scuba gear but magical," Seamus said. "Like a charm or something."

"Something that could withstand a possible fight," Ron said, tapping his chin. "I doubt Harry's going to have to go on just a treasure hunt. There will probably be obstacles of some kind in the Black Lake. I mean, for all we know he might have to fight the mermaids!"

"Lisa, could you help me learn everything there is to know about mermaids?" Harry asked. "I'm probably going to have to learn what other creatures reside in the Black Lake in case I come across them."

Lisa beamed at being asked.

"Of course, I'll help," she answered.

The door to the bathroom burst open.

"What is going on here?" Professor Snape demanded as he, the Heads of House, and Dumbledore marched in. "One of the ghosts said it sounded like a party in here."

"You are not allowed in here!" Sprout scolded them.

"It wasn't me!" Myrtle wailed, disappearing down the drain as the students hauled themselves out of the tub and began drying themselves off.

"Ten points from each of you," McGonagall scolded, herding them out of the bathroom. "I have never seen such blatant disregard for the rules! What on earth were you all doing?"

"Having a pool party," Harry stated, drying off the Golden Egg.

"Don't get cheeky with me, Mr. Potter!"

Under the disappointed glares of their Heads of House, the students were escorted back to their common rooms with points taken and detention handed out.

Aria sighed as she closed a library book a bit too hard, earning a sharp look from Madam Pince. She whispered an apology to the witch before turning a pout to Harry, Ron, and Hermione who also had their heads in books. Deciding she was too frustrated from figuring out how to help Harry swim for an hour underwater, she pulled out her own research notes for her research into a cure for lycanthropy. She had updates to some of her questions.

First, the wizarding world did do blood tests, but the spells were tricky and only healers and mediwitches ever learned them. Second, a lot of people usually had their blood read in the presence of a medical professional who not only read the blood but disposed of it immediately as there was a lot of dark magic that could be done with blood. Over the holiday break, in between the Yule Ball and doing homework, Aria had gotten Remus to send a vial of blood and with the help of Professor Snape and Madam Pomfrey, had gotten a read on his blood. It had taken a while, a lot of medical books, and some swearing on Professor Snape's part, but they had managed to isolate a magical component within the blood stream that was not in her blood, Snape's blood, or Madam Pomfrey's blood. Over the new year, Professor Snape had gone abroad to speak to some werewolf packs in Norway and had convinced a few to let him read their blood to see if their blood had the same magical anomaly that Remus had. They did. So, it was pretty certain that this magical anomaly was the lycanthropy curse coursing through their bodies.

Professor Snape was now having Aria write up the findings in an essay. There was a lot of recording and writing when it came to potions research, she was finding.

Now during the next full moon, before he transformed, Remus was going to get some of his blood drawn to see if the magical anomaly changed when Wolfsbane was added to the body.

Aria was also looking at how runes could be used. Just before break, they had begun learning in Ancient Runes about the history of using runes with potions. Aria had asked Professor Babbling if she had resources that might help her research, and she was still waiting for her professor to get back to her on that.

"Well . . ." Hermione's head popped up from behind the large tome she was studying. "I've discovered there's a Bubblehead Charm where if you cast it, it creates a bubble of clean oxygen over your nose and mouth. The only downside I can see if that it's an actual bubble, which means it could pop while you're underwater."

"And it would be difficult to recast it under the water," Harry muttered. They fell back into silence.

Aria tapped her quill against her notebook. If she were to use runes to help with her potion, she would have to determine not only what runes to use, but what kind of cauldron to use because runes were usually etched into the cauldron and the different metals created wildly different outcomes . . .

"I think I found it!"

The whisper was intense and excited and came from Neville who appeared so suddenly by their side that Ron nearly fell out of his chair. Neville was nearly vibrating.

"What?" Hermione questioned. "Come on, Neville, spit it out!"

"Gillyweed!"

Aria drew a blank.

"What is gillyweed?" Harry asked after a minute of Neville not elaborating.

"It's a plant," Neville answered, a bit unhelpfully. He took a deep breath and kept going. "It grows in both fresh and salt water. But if you consume it, a person will grow gills and be able to breath underwater. Quality gillyweed will let you breath underwater for about an hour."

"You say about," Ron drawled. "That means Harry would have to find whatever it is that is missing before the gills disappear."

"Correct."

"And do we know how long each batch will last?"

"No." Neville grimaced at that. "You can't tell until the gillyweed no longer works."

Harry grimaced at that.

"How does a person get gillyweed?" Aria asked.

"Specialist apothecaries or herbologists who cultivate it," Neville said. "It's not native to Britain."

"Well, seems like a visit to Professor Snape is in order," Ron said, closing the books in front of him. He froze after a few seconds. "I can't believe I actually said that!"

Aria rolled her eyes as she and Hermione gathered the books and put them all on the returns cart so that Madam Pince would not have to collect the books herself. The witch gave them a smile of thanks as they passed. Neville veered off towards the greenhouses while the four of them continued down into the dungeons to Snape's office.

Professor Snape was grading a stack of rolled parchments. From the amount of red ink being used and from the deep scowl on his face, Aria concluded he was either reading seventh year essays or first year essays.

"This had better be a question about your essay on the properties of the Sicilian Lava Worm and its use in warming potions," Snape drawled, not looking up as he made a horrible slash of red ink through an entire sentence.

"Can I borrow some gillyweed?" Harry asked. Aria almost groaned. So much for subtle! And Harry was supposed to be a Slytherin!

Snape's hand paused and he gave a very longsuffering sigh.

"No," he said.

"Please?" Harry wheedled. Snape put his quill down.

"What do you want gillyweed for?" he asked. "It cannot help you on your fifteen inches about the properties of the Sicilian Lava Worm."

"No," Harry answered, elongating the word. "But it can help me breathe underwater and I need to be able to in order to complete the Second Task which is in only three weeks now."

Snape's eyes rolled to the ceiling and Aria thought he might be praying.

"I don't have any gillyweed," Snape finally answered. "Nor would I be able to give you any as a professor. The rules state that I cannot help a champion."

"Oh please!" Hermione cried. "As if Fleur and Viktor aren't getting help from their professors and Heads of School."

"So Mr. Potter and Mr. Diggory compete with the moral high ground," Snape replied. "Not any of my business. But if a particular student who is currently doing potions research would need to possibly order some from Loughty's Imported Plants out of Hull, that is where I would go as they will have the freshest on hand with the highest attention to quality."

"Got it!" Aria cried. "Thanks, Professor!"

"Please see yourselves out."

"I swear, you have a strange relationship with your Head of House," Ron said once they were in the corridor. Their new direction was to the owlery for Aria to write to this Loughty's Imported Plants.

They were stopped by Professor Babbling just before they left the castle. She handed Aria a few books.

"These are the resources you asked about," she told Aria. "However, I was looking through the information I have on former NEWT students for Ancient Runes and I believe Frank Treworgy has decided to pursue a mastery in Ancient Runes. He was a Slytherin during your first year or two at Hogwarts."

"I know him," Aria replied. "He married Teddy Lawrence."

"Did he now? Well, they were always good friends."

Professor Babbling left them. The four continued on their way to the owlery. There Aria and Hermione crafted a letter to Loughty's Imported Plants while Harry and Ron spoiled Hedwig with treats and pets.

"No letter to this Frank Treworgy?" Ron asked as Aria attached the one letter to Hedwig.

"I think I'll need to think over how to word the letter," Aria admitted. "I don't want to send him something vague. We haven't spoken since he left Hogwarts."

And she had plenty of time to write out the perfect letter anyway, Aria reminded herself. Nothing could really be done until she knew whether or not Wolfsbane had any physical effect on the magical anomaly in the blood of a werewolf. She did, after all, have two weeks left before the full moon and those answers.