"So it will be me, Cleo... and Bella and Rikki... And a few other people too," Emma said to her parents. She was trying to convince her parents to let her go to Rita's house with Zac and everyone else.

"I don't know Emma," her Mum said, drying up the plates from dinner that day. "How long will the trip last?"

Emma paused for a moment. "No longer then three days," she replied, though it sounded more like a question.

Emma's mother sighed.

"She's growing up," Emma's Dad called from the sofa. "Maybe we should let her go."

Elliot, Emma's younger brother looked up from reading his book. "Can I have Emma's room?"

"I'm not going away for ever," Emma told him.

"Who knows?" Elliot grinned. "You might like it so much you don't want to leave."

Emma shook her head. "I don't think that would be the case."

"When will you be leaving?" Emma's Mum asked, picking up a pottery cup from the drying rack.

"Tomorrow."

Emma's Mum almost dropped the cup. "Tomorrow? That's a bit short notice, don't you think?"

"I only got told today," Emma shrugged.

Emma's Mum looked to her husband, and sighed. "You best go and pack then."

Emma smiled. "Thank you!!" She planted a kiss on her Mum's cheek before running up the stairs and into her bedroom.

*****

The next day Emma and Cleo were walking down to the café together with a small suitcase each. There they were meeting Lewis, Zac, Evie and the rest of the mermaids. Emma had received a call from Zac, saying that Sirena and Bella seemed to be okay, but Rikki wasn't making any improvement.

"Poor Rikki," Cleo sighed.

"I know," Emma agreed sadly.

"Do you think this Rita person will be able to help her?" Cleo asked.

"Hopefully," Emma responded. "They were her potions that made Rikki like this, she must have a cure."

Cleo and Emma turned the corner to the café, and they saw Mrs Chatham. She wasn't looking at them, she was looking out at the sea.

Cleo and Emma looked where Mrs Chatham was looking, and they was a white boat, by Mako Island.

"Who does that boat belong too?" Emma asked.

Cleo had a feeling something bad was about to happen. She recognised the boat, but she couldn't remember who it belonged too...

"I'm not sure." Cleo looked in the side pocket of her suitcase. "But I think I've forgotten my phone..."

"Really!?" Emma asked, unimpressed.

"I'll run, I'll be no more then five minutes." Cleo handed her suitcase to Emma, and Cleo turned on her heels and ran.

Emma rolled her eyes slightly, and turned back to walk to the café.

Mrs Chatham had gone...

*****

Cleo's phone was actually in her pocket, but she ran down to the docking station, to get another look at the boat. She just needed to get closer...

Cleo paused for a moment, and looked around. There was no one to be seen.

Cleo knew what she was doing was dangerous, but the boat was drawing all her attention, like a magnet to a scrap of metal. She had to find out who it belonged too.

Cleo dived into the water, grew her tail and swam towards the white boat, flipping her orange fin as fast as she could.

When she got to the boat she swam to the back and found the metal leaders connected to the boat. Cleo grabbed hold and pulled herself up the rungs, so she could listen if anyone spoke.

She listened carefully. She could make out a few words spoken by a female, like "Mako" "fish" and "microscope".

Cleo felt like the voice was so familiar, but she couldn't put a name or a face to it. She sighed, and ducked her head back under the water, and swam back to the land.

Cleo broke surface and looked around, no one was there. She was about to pull herself onto land, but she saw a pair of shoes step in front of her.

Frozen with fear, Cleo managed to raise her head slightly. There, smiling down at her, was a girl Cleo thought she'd never see again.

"Careful Cleo," Charlotte grinned. "You wouldn't want someone to see your tail."

Cleo's eyes narrowed. "Charlotte."

Charlotte flashed an evil smile. "It's been a while."

At one point, Charlotte and Cleo hadn't been friends. Cleo had broken up with Lewis after their relationship hadn't really worked out, and Charlotte started dating him. But Cleo and Lewis were still friends, which caused Charlotte to become jealous. This eventually lead to Charlotte bullying Cleo, and Cleo had tried to run away. Lewis broke up with Charlotte, and he and Cleo got back together.

Cleo slowly backed into the water. "What are you doing here?"

"Oh, just enjoying the sights of Mako with my good friend Linda Denman."

Cleo's eyes widened as she turned her head to look at the white boat, memories flooding back to her. "You know Dr Denman!?"

"Of course," Charlotte shrugged, like it was no big deal.

"And you're sightseeing on Mako?"

"Yes, we found a lovely, magical chamber in the rocks of the volcano."

"The Merman Chamber!?" Cleo gasped.

"Yeah, speaking of mermen, we met one of those too..."

Cleo sighed and closed her eyes. "Erik?"

"Yes! That's him!" Charlotte smiled.

Cleo tried to duck back into the water, but Charlotte grabbed onto her wrists tightly. "Not so fast."

"Let go!!" Cleo tried to pull away, but Charlotte tightened her grip.

"Not until you've paid back for what you did to me," Charlotte snarled.

"I haven't seen you in years!" Cleo protested.

"What about the last time time we met? On the full moon, in the Mako Moon Pool?" Charlotte said.

Cleo's memories of that night came rushing back to her, after she had spent so long trying to push them to the back of her mind. Or was, in fact, herself, Emma and Rikki who has removed Charlotte's mermaid tail and powers.

"I was more of a mermaid then you, Emma and Rikki put together," Charlotte exclaimed. Then she smiled. "Speaking of which, how is Rikki?"

Cleo tried to pull away again. "Not so fast, Cleo. We still aren't done with you."

Cleo looked up, to find Erik had walked up to Charlotte. She crossed his arms and smiled down at Cleo.

Cleo sighed. "Oh dear..."

*****

Emma entered the café with hers and Cleo's suitcase. Everyone was already there, except Rikki, who was in the car.

"Emma," Evie said, walking up towards her.

"Hi," Emma said. "Can you do me favour, and take Cleo's case? It's quite heavy."

Evie held out her hand and took the case off Emma. "Where is Cleo?" She asked.

"She has gone back home, she forgot her phone," Emma replied.

Everyone was ready to go, they were just waiting for Cleo to arrive. Almost half of an hour passed, and she still hadn't shown up.

"This is ridiculous," Lyla sighed.

"She's not answering her phone either," Zac sighed, ending the call.

"She hasn't replied to any of my texts," Bella looked at her phone.

"Or mine," Lewis was looking at his phone.

"I hope she's alright," Emma said, worriedly.

"Rita isn't answering either," Evie told them, her phone still pressed to her ear.

"She'll be in a meeting or something," Sirena shrugged.

Mimmi was looking through the potions Rita had given her. "I still haven't been able to concoct anything to make Rikki feel better."

"You'll find something," Ondina said reassuringly.

Just then Lewis's phone bleeped. Everyone tuned to look at him as he held his phone up.

"Maybe it's from Cleo," Lewis said.

"Is it?" Zac asked.

Lewis checked his phone. "It's an unknown number," he said.

"Is it a call or a text?" Evie asked.

"Text," Lewis responded.

"Read it," Bella urged him.

Lewis did. "Guess who's back?" Lewis read the text out loud.

"What is that supposed to mean?" Nixie responded.

Just then Lewis's phone bleeped a second time.

"I've been sent a picture from the same number," he said.

"Open it," Lyla said.

"Is that a wise thing to do?" Mimmi said.

"What has he got to lose?" Lyla shrugged.

Lewis opened the picture, and he was met with a photo of Charlotte and Erik together.

Lewis almost dropped his phone.

"What?" Ondina asked.

Lewis turned his phone around, and everyone crowded around the phone.

"That girl... She was in our vision," Mimmi said to Zac.

Zac nodded back.

"And she's working with Erik?" Ondina asked.

"Who is she?" Evie asked.

"Her name's Charlotte... She used to bully Cleo..." Lewis paused. "... And she's my ex girlfriend."

"Well, I think I know where Cleo is," Nixie said, her eyes fixed to the screen.

"You think they've taken her?" Bella asked.

"But why would they do that?" Sirena questioned.

"I understand," Mimmi said. "First he took all our moon stones-"

"Except for Sirena's," Ondina added.

"And then Rikki drank the potion I made Erik, and now Cleo is gone? Erik is picking us off one by one, and making us weaker as a group," Mimmi finished.

"We have to get back to Rita's," Zac said. "Now."

Emma and Bella grabbed the suitcases and everyone ran outside to the car. Zac opened the boot and the suitcases were hurriedly put in.

Rikki woke up. "Is it bad that I can't remember my grandma's name?" She asked no one in particular.

"The car's a bit small for all of us, don't you think?" Emma said.

"We won't use the car," Ondina said. "Sirena, can you use your ring to transport us back to Rita's?"

Sirena smiled and held up her hand, presenting her ring. "Of course I can."

"I'm coming too," Lewis said.

"No Lewis, this will be too dangerous," Zac said.

"I'm coming!!" Lewis repeated. "Erik and Charlotte have got Cleo! And if anything happens to her-"

"Lewis, you can't come," Lyla shook her head. "You have no magic- sorry to break it to you- but Erik does. Erik is probably more powerful then all of us put together. We can't protect you as well as ourselves."

"I don't care!" Lewis cried. "I can't let anything happen to Cleo."

Zac and Lyla looked at each other (Evie watching them closely) and sighed.

"You'll have to stay at Rita's," Zac explained.

Lewis nodded. "I will. I just want to help."

Mimmi held out her hand. "You'd better come then."

Lewis smiled and took hold of Mimmi's hand. Mimmi then held hands with Ondina, who held hands with Emma, who held hands with Lyla, who held hands with Zac, who held hands with Evie, who held hands with Nixie, who held hands with Bella, who held hands with Sirena, who held up her ring, ready to cast magic.

"Wait!!!" Will suddenly appeared out of nowhere and up to them. "I want to come too!"

"Ahh, you're here now?" Lewis asked him.

"Fine," Sirena sighed. "Hold Lewis's hand."

"I'm not holding Lewis's hand!!" Will pretested. "Who do you think I am?"

They quickly moved places, so Will and Lewis were both holding Mimmi's hand.

"Will, grab hold of the car," Sirena said.

Will touched the car. Sirena checked to make sure no one was looking, smiled at Bella (who smiled back) and waved her hand with the moon ring on.

There was a blinding flash and a cloud of smoke, but when it cleared, the group were looking at Rita's house, the car with Rikki inside was behind them.

"Time to sort out Erik," Zac said.