Jin Hae's mermaid family were enjoying themselves in a lagoon. It was time for them to go home. "Come along, everyone!" the king called. His family jumped back into the open sea. They were heading for home when they hear a sound coming from the distance. It was Geun Bin's boat! "There they are! Cast the nets so that they won't escape!" he ordered. The sailors did as they were told. They threw a big net, surrounding them. "Oh no! We're trapped!" cried Narissa. Nadine comfort her daughters. The king had no triton to break the nets. They tried to go underwaters to escape but everywhere was surrounded. 

Soon, the whole family were taken aboard the boat while inside their nets. "Help!! Help!!" they cried. Geun Bin was proud of himself. "Don't worry, you creatures. We'll take you to your new home as soon as possible." Jin Hae catch up with the boat, along with Kyuhyun and Ahra. But it was too late. Geun Bin and his men have captured them. "Oh no! What shall we do?" asked Ahra. "Don't worry. We can still save them," said Jin Hae, filled with hope. "Come on, Kyuhyun. We'll go on board. Ahra, you stay here and watch the boat."

Kyuhyun climbed up the boat with Jin Hae on his back. "Stop right there, you thieves!" Jin Hae cried as she climbed down. Her tail was turned back to legs. "Stop them!" shouted Geun Bin. His goons ran towards the couple. Kyuhyun and Jin Hae faught their best. Then, Kyuhyun has an idea. He passed a small pocket knife to Jin Hae. "You go and cut the nets and free your family. I will distract these losers," he instructed. Jin Hae nodded her head, as she agree with his idea. She ran with her feet could carry and rescue her family.

"Marina!!" they cried. "You've come to save us!" said Arianna. Jin Hae was happy to see them. "Come on! Let's get you out of here!" She uses the knife to cut through. Unfortunately, it's not enough to cut all the ropes. Her hands were getting tired. King Neptune has another idea. "Marina, go to my throne room and get my triton. It will help to break these nets," he told her. Kyuhyun was also getting tired from the fighting. "Jin Hae, I don't think I can go on like this any longer. These men are strong." 

Jin Hae just smile. "Change of plans. You get back on the speed boat with your sister. I will go underwaters to fetch some powerful object," she said. Kyuhyun did as he was told. He has no idea what she's going to find but he trusts her. Ahra was surprised to see her brother. "Back so soon? Where's Jin Hae?" she asked. "You'll see later," Kyuhyun replied her. 

Jin Hae jumped back into the sea as a mermaid once more and swam back down to her adoptive home, the palace. She quickly swim to the throne room and grabbed the triton. Then, she swam up to the surface and cast a magical power using the triton on the nets. Finally, the mermaids are free. "What?! How did this happened?!" Geun Bin shrieked as he saw the mermaids are free from hostage. Arianna and Narissa angrily smacked his face with their tails and jumped into the sea with their parents. 

Nadine hugged her adoptive daughter. "Thank you so much! You saved us!" she squealed. Her daughters also came and hugged her. "Thanks a lot." King Neptune slowly swim towards her. "Thank you. You came back just to save us," he said in a soft voice. Jin Hae just smile. "I had to. I love all of you, even though I'm just your adoptive daughter in the family." She gave back the triton to the king and he destroyed the net. "Yay!" everyone cheered. Kyuhyun and Ahra happily hugged each other. 

Jin Hae swim back to the motorboat where the siblings are waiting. She climbed onto the boat and she became a human. "Finally! Our job here is done!" she said. Geun Bin sneered at the three friends below. "You won't get away with this!" he shouted. Jin Hae smirked. "Oh, but we already have." The boat began to sail away, leaving them behind, laughing. "Looks like he won't have any attractions