A New Mermaid (新マーメイド Shin Māmeido) is the first episode of Mermaid Chronicles.
Nila and Sirena are swimming in the sea, Nila collects corals and seashells, then they return to Nila's House and shows their treasures to Coralia. Then Coralia reminds them that this is the time to go to school, the girls take their stuff and swim to their school. Then they comment about the exercise they had to do for today, Nila also comments about the difficulty of their math exercise mostly about the second question and Sirena talks about the new girl coming to their school. A black car comes and Kimiko come down of the car and says goodbye to her parents and "I love you" and they responds "we love you".
Emilia sees the new girl and notice that she seems to be wealthy (because of her clothes, car and bag) and makes Kimiko fall by putting her leg in the way, Nila and Sirena comes rescue her. They talk to Kimiko and learns more about her, Kimiko talks about her "legendary klutziness" and suddenly fall and she says "told you!". At lunch, Nila talks about how unlucky Kimiko is and Emilia comes and mocks her about her dress, Nila says that unlike Emilia she doesn't change her bag every morning but she responds that she dresses better than her. Nila, upset, sees a boy coming with his plate, she uses her powers to make his glass of water fall of, Emilia is spilled by the water and everyone laughs. Sirena says "good job" to Nila and they go eating.
After school, the girls talks about their new exercises and Nila wants to swim to go home, Kimiko her, goes home by car. Kimiko asks her father if she can take his electric boat to visit, her mother asks her why she wants this, and she says that she want to visit, he says yes and she says "I love you" and they respond by "we love you". She then goes visiting the ocean, but she lost herself, she sees an island and goes there, she come down of the boat, she visits and sees an entrance, she takes it and is led to the Moon Pool. Night came, and the moon reflects on the water, it goes a mystical blue, she touches the water and watches the moon. But as she approaches, she slips and fall onto the moon pool, the moon then flashes. Later, she finds her way out of the entrance and takes the boat. The next morning, she brushes her teeth and washes her hands but before she had the time to dry them, she transforms and she notices that her legs are replaced by a pinky tail! At school, when she tried to drink from the faucet, while approaching her hand, it opens but she has no idea how it opened without touching the button. She meets Nila and Sirena on their way but acts strange before them and goes to the girl toilet. Kimiko again opens the faucet using her powers but because of a bad maneuver, splashes her and transforms. Hearing a scream, the girls run to the girls toilet and they see Kimiko as a mermaid! With dismayed looks, Nila and Sirena sighs and Nila says: "so we have a new mermaid to care about". And Kimiko watches them and do a little uneasy smile.
- Nila receives her Moon Necklace.
- Kimiko is new in the town.
- Kimiko becomes a mermaid.