Akari Mizunashi, at the age of 15, has left everything behind to travel to Aqua, a sparkling planet covered in water. More than anything, Akari wants to be an "undine" - a female gondolier who navigates the canals of the Aquan city of Neo-Venezia. As she begins her training with the prestigious Aria Company, will she be up to the challenges that await her on the path to achieve her dream?

One morning, Akari wakes up to find the entire city flooded with water! It's the Acqua Alta, a once-a-year phenomenon where the water levels rise, causing all of Neo-Venezia to shut down for a day. But while most people spend the day relaxing, Aika's mentor Akira is as strict as ever, and yells at her to get back to training. Aika has just the solution to get her mentor off her back: she's running away to the Aria Company!

While training in a particularly tough stretch of water, Akari and Aika meet girl from Orange Planet who seems to be having no trouble at all. Her name is Alice, and she's famous for being one of the youngest yet most talented Undines in Neo Venezia. There's just one problem... she never seems to smile. What could she learn from a day spent with the unlikely pair of Akari and Akatsuki?

Akari and President Aria are wandering through the marketplace one evening, when President Aria suddenly leads Akari to a plaza she's never seen before. There, a little girl with a bell around her neck gives Akari a letter, and asks her to deliver it. It seems very important. But if Akari's going to have any chance of keeping her promise, she'll have to enlist the help of flying messengers known as Sylphs!

When Akari was little, she was certain that Neverland was a real place. As she grew up, she understood that it was fantasy... But now, she's received a mysterious, hand-written invitation to visit Neverland for herself! What awaits her as she follows her map toward a quiet, deserted island?

Alice is in a pretty bad mood. Her dorm doesn't allow pets but she's secretly taking care of a kitten; her mentor Athena is an absolute clutz; and to top it all off, she has decided that her left hand isn't as skilled as her right hand, and is therefore useless. Though Alice certainly does have a strange set of problems, and they all seem separate from each other, she's certain to discover that the answers to each all are connected.

Akari, Aika and Alice are scheduled for a full day of training with Akira, and what's more, two customers will be along for the ride. They're a couple on their honeymoon; but while the wife loves Undines and riding on gondolas, the husband thinks being an Undine is simple work, and couldn't really care less about the whole thing. It's up to Akira to teach everyone what it means to be an Undine - Undines-in-training included!

It's a double dose of President Aria! In "That Melancholy President...", it's cleaning time for the Aria Company, and President Aria wants to help out and lead by example for his company. Yet he can't seem to do anything right, and only gets in the way. He's so sad about it, that he's determined to run away... but where will he go? And in "That Cool Hero...", we get to see President Aria's cute crime-fighting alter-ego: Nyan-Nyan-Puu!

Fall has arrived in Neo-Venezia and the girls have switched into their winter uniforms. And yet, Aika feels so unmotivated... She wants to do more than just go through the motions of everyday practice. She wants to really sharpen her skills, and become as good as the legendary Great Water Fairy, the greatest Undine of all time! So the three of them are sent to go visit this legendary lady in her house out in the country... but she's nothing like what the girls expect.

Winter has come - the mornings are crisp and cold, and it's hard to get out from under the covers to go practice sculling. So as a special treat, Alicia suggests that they visit a hot spring! Akari's never seen one before so she's excited to go, and all the others decide to join in as well.

On one bleak winter day, when the clouds are thick and the snow is gently falling, the girls finish their sculling practice to find that Alicia, Aika and Athena are all together at the Aria Company, sitting around the fire. Over cups of hot cocoa, they discuss their younger days, and how it was that they all came to be friends.

Aria Company has no bookings on a snowy day, so Akari and President Aria visit the oldest bridge in Neo-Venezia. When they reach the other side of the decrepit covered bridge, the snow is gone, and the women she meets on the other side has no idea what an undine is. Together they wait for the terraformers to send water under the bridge for the first time.

It's time to ring in the new year, and everyone in Neo-Venezia has come together to celebrate! Even little Ai has come back from Manhome to take part in the winter festival. But as people gather and memories are shared, President Aria suddenly wanders off. Akari and Ai attempt to track him down, but what they find is a mysterious New Year's gift from Aqua itself.

Two wonderful things have happened: it's time for Neo-Venezia's annual Carnevale, and Ai has come back to Aqua for a visit! As Akari and Ai wander through streets full of bright colors and beautiful masks, they catch a glimpse of Casanova, the mysterious master of ceremonies. Who is the man behind the mask? The two are curious, but they'll need to be careful. You know what they say about curiosity and the cat, after all...

Spring is beginning to bloom in Neo-Venezia, bringing with it sunshine and warm breezes. Akari, Aika and Alice are out practicing their sculling when they find a small treasure box hidden by a statue. Inside there's a a simple little riddle that sends them off on a treasure hunt that spans the entire city! What sort of riches await them at the finish line?

There's going to be a meteor shower, and Akari, Aika and Alice have made plans to watch it together. But this time, there's a little twist - Al, one of Neo-Venezia's gravity-controlling Gnomes, will be there as well. Even though he's shorter than the girls, he's actually three years their senior; and he knows all about physics, planets, and the beauty of the universe. What he doesn't seem to know, however, is how Aika feels whenever she's with him.

The mailman's gondola is being repaired, so just for today, Akari is making the rounds with him to get the job done. As she learns the ins and outs of what it means to be a mail carrier, she meets a boy who needs his letter delivered at any cost. Whatever the envelope he's holding contains, it's very close to his heart.

Akari and Alicia are visiting a shrine that looks just like the old Japanese shrines on Manhome. Though the grounds are beautiful, there's also a hint of mystery and danger in the air... Later, they are wandering on a different island, looking for a beautiful spot that Alicia once saw. But the farther they go, the less certain their path becomes. How do you reach your destination when you don't know the way there?

Something's strange about Alice... Athena has noticed that Alice doesn't really seem to have any friends her own age. If she's not with Akari and Aika, she's simply alone. In fact, when Alice receives an invitation to a party with other Orange Planet Pairs, she flatly rejects it. It's up to Aika and Akari to get to the bottom of Alice's puzzling behavior.

While practicing one day, the girls see President Aria in his own little gondola. But he doesn't see them... instead, he disappears down a canal that's normally closed off. According to Alicia, there's an old legend on Manhome that tells of the Kingdom of Cats, a strange realm that people aren't allowed to enter. Could such a place really exist?

Another wonderful holiday has arrived: Festa Del Bocolo! This day is a celebration of an ages-old story on Manhome, about a knight whose love for his lady lived on after his death in the form of a rose. In Neo-Venezia, that means that women everywhere receive roses from the people who admire them. Akatsuki wants to give Alicia as many roses as he can, but he's too nervous to deliver them (even though he'd never admit it). Will Akari be able to help?

Akari is taking customers out for a tour! Alicia is along to help, of course, and it's a good thing she's there. When the tourists start asking questions that Akari doesn't know the answers to, Alicia answers them with ease... but this worries Akari. Will she ever know the city as well as Alicia? This sparks a fire in Aika and Alice as well - they've decided to compete to see which one of them knows the most hidden wonders in Neo-Venezia.

Even though Akari is originally from Manhome, she seems to know more people in Neo-Venezia than Aika and Alice do, and they've lived on Aqua all their lives. No matter where she is, Akari has the ability to befriend any stranger. To learn more about this mysterious power Akari has, Aika and Alice decide to follow her in secret... but they might have to blow their cover once Akari innocently starts talking to a dangerous-looking man in black!

Akari has been given her very first solo job: carrying a shipment of Neo-Venezian glassware. They're beautiful pieces that sparkle in the sun, but the glassmaker's apprentice has a disposition that's anything but bright. He's sour and angry, and he's the one who'll be traveling with Akari as she delivers the shipment. Will Akari be able to handle the pressure of fragile cargo and a critical taskmaster?

Summer is blazing in Neo-Venezia. The days are so hot that Akari is starting to see things... One minute, she's walking down a crowded street, and the next, everyone is gone. Following President Aria in a haze, Akari wanders into a mysterious cafe, with a very unusual clientele... Later, the girls all decide to buy Nightshine Chimes, delicate little wind chimes with a glowing bead inside. The glow only lasts for a month before it fades, so Akari decides to make the most of the time she has.

Alice has created a new challenge for herself: when she walks home from school, she can only step on shadows. This is an ironclad law for her - but try as she might, she keeps failing. Even worse, Athena interferes by trying to help out. Alice's self-imposed challenge is something that she must conquer alone, or so she thinks; but maybe there's more to success than just doing everything by yourself.

Many of the water touring companies in Neo-Venezia have their own palina - a tall, decorated pole used to hitch gondolas. But strangely, the Aria Company doesn't have one. When Akari asks Alicia about it, Alicia gives her full permission to make a palina of her own! It's tough work building something from scratch, but Akari is determined to make the best palina possible.

Even though Akari is relatively new to Neo-Venezia, most of her friends have lived in the quiet island town all their lives. One sunny afternoon, as Akari, Akatsuki, Akria and Al are all eating lunch together, Al tells a story about when they were children, and the mysterious young boy who put Akatsuki squarely in his place.

When Akari takes her gondola in for a routine inspection, she's given some startling news - the repairman tells her that the gondola is now too old and worn for tourism use, and should be sold off for hauling cargo. Although she at first resists, Akari knows that the repairman is right; so she decides to travel with her gondola to all the wonderful places that she's been, as a way of saying goodbye.

On the night before her old gondola is set to be taken away, Akari and Alicia decide to have an evening picnic out on the water. As they laugh and talk, Alicia tells her stories of the gondola, and how it was an important part of her life as an apprentice, as well.

Aika is proud of her long, beautiful hair, and takes care of it as best she can... but things don't always go the way we want. One afternoon, while everyone is enjoying a cook-out on the beach, Aika leans in a little too close to the grill, and her hair catches on fire! No one is hurt, but her long beautiful locks are a lost cause. How will the hot-tempered Aika handle losing something that was so precious to her?

Aika is stuck in bed after catching a cold. She wonders about Akari and Alice... Are they slacking off without her? Surely they're lost without her guidance! So she sneaks out of bed one day to go take a peek... Later, Aika has a cute new set of hairpins, and she'd like to show them to Al. But she can't find the chance to visit him, and it's bothering her more than it should. Why does her heart ache when she thinks about it?

The whole town is sizzling in a strong summer heat wave, and the girls are doing the best they can to beat the heat. But then, Akari spots a woman dressed all in black, with even her face covered with a thick black veil. Aika tells Akari a Manhome legend about the spirit of a woman dressed in black, who was angered that she couldn't be buried on San Michele Island. Supposedly the ghost spirits away any gondolier foolish enough to take her on board... but that's only an old story, right?

In the still of the night, Akari is woken up by the distant sound of a train. But Neo-Venezia's trains don't run at that hour, so what was it she heard? And to make matters even more mysterious, the next day, President Aria gifts her with a train ticket. It would seem Akari is about to have another brush with the secretive spirit, Cait Sith...

When Akari innocently suggests that perhaps the little space between two stairs at the Aria Company is a portal to another world, President Aria, ever curious, squeezes through the gap, and pops out on the other side to find a terrifying sight! The second story is a flashback to when Akatsuki was little. He considered himself to be a superhero, but he wasn't quite as heroic as his imagination led him to believe...

As summer begins to wane, Alicia and Akari give a tour to an elderly couple who have come to Neo-Venezia to celebrate their anniversary. Although the woman is sweet and charming, the man is a bit of a grump. He orders her around, doesn't seem interested in sightseeing with his wife, and just acts cranky in general. But things aren't always as they appear... Even though he's tough on the outside, he still wants what's best for his wife, and it's up to the girls to help him set up a celebration that she'll remember always.

Heavy rain keeps the girls from their usual gondola practice, so instead they spend the day at Himeya. They start off studying at first, but when their minds drift off to what nicknames they'll take as Primas, Akira steps in and gives them some good old-fashioned paperwork to do. Even that can't get Aika down, however... because she's noticed lately that people whisper to each other when she walks past. Does that mean she's finally being recognized for her skills as an Undine?

Akari, Aika and Alice have been given their latest assignment: they must host a party on the Festa del Redentore! It's a festival that marks the start of autumn, and it's celebrated with feasts and fireworks. They rent a large boat, and start brushing up on their hostess skills, but Akari can't help but be a little distracted. She hasn't heard from Ai in a while, and all her emails have gone unanswered...

As winter melts into spring, Akari, Aika and Alice all continue to practice and set new goals for themselves. But Akari still feels like she isn't good enough to become a Prima. Will she or any of the girls ever be truly satisfied with their talents?

Someone has requested Akari for a gondola tour! An old woman with a kind smile says that she'd like to see a side of Neo-Venezia that only Akari can show her. Akari takes her to many unique spots, but the woman already seems familiar with them all...

A new vendor has opened up shop in Piazza San Marco, selling heart-shaped chocolates in glass bottles. Akari buys a bottle, and later goes to buy another, but by then, the patissier has mysteriously disappeared. Where did he go, and will he ever return?

Akari wants to help out more around the Aria Company, but she's only a Single. So Alicia suggests she try her hand at working on a Traghetto! A Traghetto is a ferry-style gondola run exclusively by Singles. Will Akari be up to the challenge?

Athena and Alicia both have wonderful talents, but what about Akira? For that matter, what about Aika? Aika gets discouraged, thinking that maybe she doesn't have any natural talent, but Akira has an old story to tell that might lift Aika's spirits.

Akari can be a bit clumsy and makes plenty of mistakes, but it seems like Alicia never gets angry with her. Alice makes it her mission to see how Alicia handles Akari's faults, and to see if it's true that no matter what, she never scolds Akari.

Akari and Alicia are going to visit Anna, the woman who trained with Alicia in the early days of the Aria Company! Many memories will be shared on this visit, including how the Aria Company itself was first founded.

Alice and Athena are going on a picnic! Alice chooses a date and makes all sorts of elaborate plans... but Athena gets overloaded with work, and can't come. Athena tries to chase after Alice to apologize, but trips and falls - and somehow loses her memory!

Alice has just graduated from middle school. She feels confident, and excited about what's to come. And then, Athena suggests that they finally go on the picnic that they've been planning for so long. Alice's world is about to change...

Akari, Aika and Alice decide to partake in an old Manhome tradition, Moon-watching. Aika secretly invited Al to their get-together, but he hasn't shown up yet. Aika goes to look for him, but she has no idea what surprises the night has in store.

Alice is so busy now; every waking moment is full of appointments and work. Though she enjoys the life she has now, she still misses the time that she spent with her friends. It's starting to feel like she might never see Akari and Aika again.

As Akari and Aika leave for practice one cold winter morning, Aika has something to tell Akari. The two of them can't practice together anymore... As if that shock weren't enough, Alicia has something important to say as well.

Over the years, the Aria Company has changed. First it was Grandma's Aria Company, then it was Alicia's, and someday, it will be Akari's Aria Company. But that day might come sooner than Akari expected. Will she be ready for the future that lies ahead?