I think this might be the fastest I've updated this story since I first published it. So, yay! Thanks for the reviews and I hope everyone likes this chapter!

Juliette POV

Juliette had a theory.

While all her fellow mermaids were kind of pissed at her for the water incident at dinner, the guys were not—well, they didn't have to worry about popping tails upon contact with water—but still. Mason, of course, was just worried about Ella. She could tell from the look on Lewis's face that he was suspicious, but she had no idea what he could possibly be thinking. It was Riley actually—the guy with the least amount of experience with mermaids—who realized something was wrong.

He pulled her aside before they climbed back on the boat and asked her about it. She told him how she hadn't purposely dropped the water on the table, how she somehow lost control over it. If she was being honest, Juliette would have to admit that she got her theory from Riley. He'd been the one to ask her on the dock if she could control any of the water below their feet. She'd tried…and failed.

Now she had a theory to test. But she couldn't do that until Ella fell asleep. She knew her twin wouldn't approve. Well, maybe approve was the wrong word. Ella would worry about her. She'd see Juliette's theory as a risk that could end up with horrible consequences. And she would be right. But Juliette was willing to take that risk. While Leah still believed Lewis was the right person to help them, she wasn't so sure anymore. At dinner, he clearly had never heard of Leah's power, and she wondered how many other mermaid abilities he didn't know about. Did he know Ella could freeze and heat water? Did he know that Marguerite could predict the weather? Did he know that Adelaide could communicate with marine animals? Did he know that Cecilia could manipulate ocean plant life? Was he really the expert everyone thought he was?

Juliette rolled over in her twin bed, listening to Ella's breathing. She counted the seconds between when Ella breathed in and when she breathed out. Two Mississippis. That meant Ella was sound asleep and it was safe for Juliette to get out of bed.

There was a certain process to sneaking out. She eased herself out from under the sheets. She was careful to avoid the spot on the floor beside her nightstand that squealed like wounded dog whenever someone put pressure on it. Tonight wasn't the first, or the second, or the third time she'd snuck out without anyone noticing, Ella included. For Juliette, who sometimes wondered if she suffered from insomnia, it was a normal occurrence. She hadn't counted but she was sure that over the summer she'd spent more nights wandering around the island than actually sleeping. She was also sure that she knew the island better than anyone—probably even better than the people who first built the school around the Crystal Lagoon. She knew that there was a cave on the north side of the island whose only entrance was to drop in from above. She also knew about the hidden nook on the east side beach where turtles came ashore to bury their eggs. And she knew that if you climbed the tallest tree beside the Crystal Lagoon at night you could see the lights of the mainland.

But tonight wasn't about exploring and discovering new wonders. Tonight was all about testing her theory. A theory that she desperately hoped was wrong.

She laughed to herself. If Ella could hear her admit that she wished she was wrong, her friend would surely die of shock.

Scooting passed a sleeping Ella and out the door, Juliette made her way down the path towards the Crystal Lagoon. She took a deep breath in, relishing the cool, salty air that flooded her nasal passages. She followed the cobblestone path until she found herself at the circle of palm trees that guarded their magical pool. Glancing around to make sure no one else was around, she slipped between the two trees with the largest gap between them.

The water in the lagoon was still, a perfect plane of blue glass, undisturbed even by a stray fly or mosquito. Above her head, the full moon shone bright against a sheet of dark blue sky. It's reflection danced and sparkled across the surface, illuminating small sections of the beach floor and hitting the crystals on the side so the pool looked like it had been doused in blue glitter.

Juliette's breath caught in her throat. No matter how many times she'd seen the Crystal Lagoon at night, the sight still awed her.

She looked up. The moon wasn't quite overhead yet. But that didn't matter. She planned to test the first part of her theory before the full moon aligned with the lagoon. The second part would come when it did.

Glancing one last time up at the moon, Juliette braced herself and then slipped into the water.

Lewis POV

"Are you sure you're okay, Cleo?" Lewis asked for what he knew was the fourth time. But he didn't care how many times he asked as long as Cleo's answer was always the same.

"Yes, Lewis," she said again.

Had he been standing in front of her and asking for a fourth time she would have glared at him and answered through gritted teeth, but, because they were on the phone and he was thousands of miles away he could still hear the smile in her voice. Lewis was smiling too. He couldn't help it. He hadn't stopped smiling since he picked up the phone and heard her voice on the other end. He'd spent the last three hours pacing his room, feeling like someone had their fist over his heart, while he waited for her to call. He didn't know how many times his mind forced him to imagine Cleo being snatched by the water tentacle. But it was enough to make him shout Cleo's name into the phone when it finally rang.

"And Rikki's okay?"

"Yeah," Cleo said, "Will was there and he saved her."

While Lewis had initially been wary about letting Will into the group, he couldn't deny that the girls were in good hands with him around. A lot better hands than had he left them with just Zane. And after what Cleo told him Zane did—on the night of a full moon no less—Lewis had never had such a strong urge to hit someone as he did when he heard the story from Cleo.

"I should have been there," Lewis said into his phone.

"Lewis, you're halfway across the world," Cleo reminded him. "Those girls need you."

"You need me more," he told her.

"I want you more," she said gently. "There's a difference."

"I know," he sighed. There was a pause on the line. "I miss you."

"I miss you too," she replied. "We're okay, really. We can handle this. Go be the brilliant scientist that you are and help those mermaids."

He smiled. "Okay. Give Will my thanks, will you?"

"I will. Talk to you soon?"

He wanted to tell her that he wanted to talk to her now, but he knew that she had things to do. "Yeah, talk to you soon. Bye."

"Bye."

He pulled the phone away from his ear, staring down at the blinking number on the screen. He'd talked to Cleo for half an hour. It was nowhere near as long as he would have liked, but then again it was three o'clock in the morning now. He supposed he should try to get some sleep before he had to get up to do more tests.

A head bobbed passed his window. He peeked outside to see Juliette walking down the path again. Only this time she was alone. He glanced back at the clock, weighing his options: should he just go to bed or should he follow her?

He elected to follow her, reasoning that the last time he'd followed the younger girl he'd discovered that there were mermaids at the institute and that hopefully he'd make another new discovery if he followed her again. But he was only hoping. He knew that if Juliette had the answer to the girls' mermaid problems she would have come forward long ago. He could see the way it physically pained her to not be able to go in the water. She wanted their problem solved just as much, if not more than he did.

He followed her, his path lit just enough by the light of the full moon overhead. Only at the end of the path she didn't take a right towards the ocean like last week, instead turning left and heading towards the center of the island. Where was she going tonight?

She led him further inland before disappearing behind a bunch of palm trees. Lewis immediately recognized the area as the place where the institute's version of the moonpool was. He looked up at the full moon. He didn't know what Juliette was doing here, but, whatever it was, with a full moon in the sky it couldn't be good. Was it possible that she was moonstruck? Well, if she was, he hoped it was the giggly harmless type of moonstruck. He didn't think he could handle any psychotic trance people tonight. He slipped between the palm trees into the circle.

Juliette was floating in the center of the pool—or, the lagoon as they called it. One look at her facial expression and Lewis knew she wasn't moonstruck. She'd come here voluntarily. And, from the looks of it regretting her decision. Her lips were pulled in and tears were gently forming streaks down her cheeks, the droplets disappearing into the water when they fell. But the sight of Juliette crying wasn't even the most surprising thing about the scene before him.

She was treading water…with her legs. Juliette was almost fully submerged in the pool and yet she didn't have a tail.

She stared at him, tears still streaming down her face, and he stared back. For once, she didn't say a word. She turned her face upward and he followed her gaze to the moon. It was almost completely overhead.

He watched as the reflection of the full moon hit the water of the lagoon—hit Juliette—and waited. Nothing happened. Juliette glanced all around her but the pool didn't begin to churn and bubble and she remained in her soaked through pajamas.

Seconds ticked painfully by. Lewis held his breath as he watched the moon's reflection slip away from the water. The magical moment when someone could be turned into a mermaid had passed. Lewis swallowed hard.

Juliette was no longer a mermaid.