It is raining heavily outside. Zac watches the rain outside the window as the mermaids discuss the plan for their next mission.

"Isn't this awesome?" asked Zac as he continued watching the raindrops fall on the window.

The other mermaids just ignored him.

"Why don't we go outside and try and swim?" suggested Zac.

"That is an incredibly stupid idea," protested Mimmi.

"Why?" asked Zac.

"As mermaids, we immediately grow tails the instant our skin contacts water. We'd be flopping around on the floor with our tails." Bella replied.

"But I thought we can swim in water?" questioned Zac.

"Yeah, but you need to be in deep water for it to work. You can't just propel yourself along a puddle or two." Lyla answered.

"Aww, I thought I could go outside and have some fun. Guess we're all stuck inside doing nothing."

"Hang on a minute, there is somewhere we could go to." Mimmi commented.

"But where is that? There's nothing in here except my room," said Zac.

"There's something I haven't told you yet. Before you were born, we all occupied this guest room. Your mother Nerissa was a powerful mermaid, and she was able to create a pocket dimension inside the attic. We've never really explored her private space before, so we figured that we might just check it out for once."

Zac and the mermaids opened up the attic panel and climbed inside the tight space. Mimmi felt around her but all she could touch were the wood panels of the roof.

"Hmm, I swear the entrance used to be around here." Mimmi spoke.

"I'll try another spot," suggested Lyla as she began crawling around the attic space.

"Be careful!" warned Bella. Lyla was too eager as she continued crawling. She accidentally hit a weak spot, and the beams underneath her collapsed. She fell straight down through the ceiling back into the main room.

Zac and the other two then climbed back down and comforted Lyla.

"Well, that was a waste of time." Mimmi complained.

Just then, Zac felt a strange sensation in his head. "Guys, something's happening to me!" he screamed.

"What is it Zac?" asked Bella.

"I don't know, I have this awfully bad headache."

"I think it might be a vision coming through," commented Mimmi. "I experience dozens of those, and I've learnt to keep a cool head."

"A vision? But why would I have that ability?" questioned Zac.

"Well, you're connected to Nerissa being her son. I was a close aide of Nerissa during the long-fought mermaid war. Nerissa being a powerful Nymph had an excellent battle plan, and she was well prepared for all our fights. I guess that's why you and I both have the power of premonition, where we can foresee events happening in the future."

"What was in that vision of yours?" asked Bella.

"I don't know, my headache was too severe to focus on anything in particular." Zac replied.

"Why don't I try?" suggested Mimmi as she held her right hand up to Zac's forehead. Mimmi then felt a sensation in her head, as she was experiencing Zac's vision.

"I think Nerissa is trying to tell us something," said Mimmi.

"What is it?" questioned Zac.

"She says that we need to find her spear. She used to keep it in that pocket dimension she created but realised that it was no longer safe. Someone has found a way to infiltrate that place, so she moved it to another secure location somewhere on Mako Island. We ought to go there and find it."

Later that day

The rain had stopped, with Zac and the mermaids then swimming out to Mako Island. They landed on the beach and were unsure where to go. Mimmi and Zac both experienced visions in their heads, and they saw that a powerful water dragon was going to make landfall on the beach.

"What did you two see?" asked Bella.

"We couldn't get anything about where this secret location is, but we saw that a water dragon will make landfall on this beach. We ought to hide in the forest and hope that beast doesn't make it inland," replied Mimmi.

Zac and the mermaids settled on the ground inside the forest. It was uncomfortable, as they didn't bring any camping gear.

"How much longer?" asked Lyla. "I really hate having to sit on this loose soil."

"I don't know," replied Zac. "I haven't got any new visions. What about you Mimmi?"

"Nope, still nothing." Mimmi added.

The group had stayed for a while, then they heard the low-pitched growling sounds. They looked back towards the beach and saw a giant water dragon emerge. Zac and the mermaids panicked as they tried to run deeper into the forest. They reached the rock outcrop marking the entrance to the secret cave, and Mimmi pointed her moon ring at the rock. The magic activated, opening the entrance.

"Quick, get inside!" yelled Mimmi.

"But what about you?" asked Zac.

"I'll try my best to hold off that water dragon. You lot just seek shelter inside!"

Mimmi then left Zac and the others alone, as she was confronted by the water dragon.

"Back off, you nasty monster!" she yelled as she pointed her moon ring at the dragon. She tried to use her flame powers to hurt the beast, but they didn't seem to work. The dragon fired a blast of water at Mimmi, soaking her and transforming into her mermaid form. Mimmi was struggling as the water dragon roared. Mimmi was afraid she was going to be killed, but then she saw a white mist surrounding the dragon. Eventually the mist subsided, and the dragon was gone. In its place was another mermaid with dark brown hair. She seemed to recognise Mimmi and walked up to her.

"Now this won't hurt at all," said the new mermaid as she thrust her arms forward and began heating up the water on Mimmi's tail. Mimmi returned back to her human form and was about to leave when the other mermaid called out to her.

"Leaving so soon are we?" asked the new mermaid.

"Who are you?" questioned Mimmi.

"You don't remember? We fought in all those battles together. You stood by my side and helped me lead the rebellion against the Homeworld Pod," replied the new mermaid.

"Nerissa? Is that really you!?"

"Yes, I never thought that this would be the time I could finally return to my private quarters on Mako."

"But what about that water dragon? You saved me from its attack."

Nerissa just laughed out loud. "Oh silly girl! That was just me in my transformed state."

"You can shapeshift into a water dragon?" asked Mimmi who was stunned.

"Yep, that's right. Now, how about we join the others in my private quarters." Nerissa spoke as she and Mimmi then walked together towards the rock outcrop.

"Wait, how are we both going to get inside?" asked Mimmi.

"That's another thing you haven't learnt yet," replied Nerissa. "I have the power to go into any secret hideout without a moon ring. As long as you hold my hand, both of us can go through that opening."

Mimmi and Nerissa then walked through the rock opening together.