The world has become a nightmare. Years ago, Emily Windsnap and her friends have brought the human and mermaid world together. The two worlds lived together and prospered for many years. But all of the joy ended when some scientists decided to do mermaid research. They kidnapped various mermaids for research. In reply, Neptune declared war against the humans and the forever war began.

Emily and her husband, Aaron, and their friends tried to maintain the harmony, but Emily and Aaron disappeared in the process. Neptune decided after they disappeared for all semi-mers to be locked away. One-by-one each semi-mer vanished and was locked away. The only problem was Emily and Aaron's year old baby girls, Atlantic and Jewel. They were twins, the same mousy brown hair as Emily, and the same thin figure. The only difference was Jewel was a mermaid and Atlantic was a human.

Neptune couldn't just lock them away because they weren't really a part of the law and they were like his daughters. He could easily keep Jewel as his daughter. But Atlantic was a human, but Neptune could never keep her. He called ; the last semi-mer not locked away, and told him to bring her to the closest house near the shore in Bridgeport.

Twelve years later, they met. The world then was difficult. No human was allowed to be close to shore. Neptune had soldiers come daily to Shiprock because it was near Bridgeport. Atlantic was your average shy nerd, with a unique sense of style. She never fit in, but she mostly spent her time studying mermaids.

Jewel, on the other hand, was the most popular mermaid at her school. She had the voice of a siren, was amazing at all her subjects, and was really pretty with her many arrays of jeweled tops. But she loved studying about humans, something really different.

Each girl had wanted to meet the other kind. Finally, Atlantic was out of it, and wanted some alone time. As Jewel was a princess and was popular, Atlantic was the maid for a mean wealthy family. Atlantic ran under the rope that closes off the seashore.

"The government need better gate for the beach." Atlantic commented.

The beach was rock-strewn, not much of sight. Neptune wanted no humans going near the ocean.

Meanwhile, Jewel was at the top of a rock above the watching land with the humans doing their things. Because she was the princess during a war, Neptune commanded for at least one bodyguard for Jewel. She just ditched her last one, telling him that she wants shrimp and tuna.

"Pretty sure Dad will fire him soon!" Jewel laughed as she swam away to Shiprock. As soon as he discovered this, he was furious. And nobody likes him furious.

"What's that?" the twins shrieked. A typhoon bigger than life appeared in Bridgeport's shore. Atlantic ran into a nearby cave, while Jewel tried to just swim away as quickly as possible.

The typhoon disappeared sometime during the night. Atlantic came out with her clothes even more torn and tattered then they usually were.

"Ugh." Atlantic said, stretching. "Who are you? Oh my gosh, are you okay?"

Jewel lay on the shore, with her tail hidden in the wave. She was groggy when Atlantic was talking to her.

"Huh? Who are you?" Jewel asked. Atlantic scrunched down and they were face-to-face.

"Who are YOU?!" they both screeched. They were just stared into each other's eyes.

"I-I'm Atlantic." shattered Atlantic. "Are you my twin?" She's never been good with people.

"Oh, I'm Jewel!" exclaimed Jewel. "And yeah, you look like my twin?" She's great with mermaids.

Then the tide washed away and showed her tail, when Jewel noticed her legs.

"You're-" they both stammered.

"How can we be twins?" Atlantic asked.

"If we look exactly alike we're twins, right?" Jewel replied.

"We need to talk. I think there's an underwater entrance to the cave over there."

They left for the cave.

"Hey, look what I found!" exclaimed Jewel when she entered the cove. She held up Neptune and Aurora's diamond ring.

"Really, I found the same ring except there's a pearl." said Atlantic holding up the ring. "Try it on!"

They both slipped the rings on.

"So what are we going to do?"

They clamped hands together.

"No clue. How we're even sisters when there's a war…" Jewel said.

"We will stick together, won't we?"Atlantic asked. "I could use a friend."

"We are sisters aren't we? Sisters stick together." Jewel replied. "And friends are side-by-side."

"That also means…"

"We need to find the truth. Swishy! I always LOVE a good adventure. Don't you?"

"I don't know… I haven't really got the nerve." Atlantic said.

"But we'll figure it out. Trust me!" Jewel encouraged excitedly.

"I have the feeling whenever you day that something bad is about to happen."

"I'm the daughter of Neptune. What do you think?"

"Neptune!? The King of the Sea?" Atlantic gasped in horror. "He's, like, the most power merman on the planet!"

"Calm down. It's all under control."

"Fine. Let's do this!" exclaimed Atlantic.