Maia Mizuki's dream is to join the Ocean Agency. She tries as hard as she can but when she is not accepted, she faces homelessness and hopelessness. Then a series of unfortunate happenings force her into a job with Neres, a security and investigation company that will also do almost anything for money. It soon becomes obvious that no one “normal” works at Neres. Shizuka is a kind, tech-crazy young woman with a passion for food; Glora is a trigger-happy, money-loving tomboy; Yuu, a quiet, brooding woman, is frighteningly deadly in combat; and Rena is the alluring, unofficial leader of this particular Neres office. With Neres, Maia faces danger and crazy situations daily; it’s almost too much for her, but Maia is strong, and she does her best to hang on and make it through this unexpected turn her life has taken.
Maia is having the worst day of her life. She is not accepted by the Ocean Agency and is kicked out of her house. Now she cannot find a job that will pay room and board. Then she is taken as a hostage and is shot at.
Maia becomes involved in a detainee exchange that goes bad. The housing agency confiscates all her possessions, so she has to join Neriads.
Maia and Shizuka solve the mystery of the Martin’s missing wedding money. Trouble is lying in wait for Rena in the form of a blonde woman.
Maia has to drive the experimental hover car for Team Albatross. Someone is sabotaging the car, so the Neriads try to find out who is doing this in order to keep Maia safe.
Maia is introduced to a martial arts expert named Yu Park. Rena and detective Yagi are taken hostage while on a cruise ship. Yu is reinstated as a Neriads agent after serving 90 days in jail and saving detective Yagi.
Maia gets partnered with Gloria, and Yu and discovers the tense relationship they have. Car thieves kidnap Maia as Yu and Gloria chase a suspicious truck.
The branch manager’s daughter discovers he has been lying to her about his role at work. The gang catches a group of poachers.
Maia takes the wheel of a test vehicle when Shizuka’s childhood friend, Millie, is injured. Maia gets caught in some industrial espionage.
Gloria is told she only has a week to live so Tsukasa now has to help her meet her ideal man.
The girls go to Siberia City where slave traders kidnap Shizuka. Maia has no recollection of being in Siberia before but knows the fastest way to intercept the fleeing kidnappers.
When Maia passes a Loral Tree, it sparks old memories from her past. Everyone decides to spend an extra day in Siberia looking for clues about Maia’s past.
Maia, Tsukasa, and Millie show off the Ocean Agency's new hovercraft. It is also the celebration of the 100th anniversary of underwater cities rising to the surface.
Wong, Chang, and Lee seek revenge on Neriads for putting the three brothers in prison. Neriads confiscates the submarine Mai stole.
Since the submarine is just sitting around and costing a fortune, Maia goes out and finds the crew a job. This job will also double as a training mission for the crew. Their job is to go searching for a sea monster.
Maia is sent to Siberia to find a runaway. A mechanic has been paid to sabotage the plane of a wealthy CEO.
Maia and the runaway boy are accused of plotting to kill the CEO; but Rena and Shizuka are able to track down the real plotters.
A baby has been abandoned at Yu's front door. Gloria does not want to turn the baby over to the police.
A con artist plays with Shizuka's heart.
Maia is taken hostage when Mai, Wong, Chang, and Lee steal the submarine again. Maia then has to rescue the treasure hunters from a watery grave.
The stress of trying to rescue the treasure hunters triggers memories of Maia's past. Maia returns to Siberia in search of the time capsule she and her brother buried under the Loral tree.
Maia is unable to concentrate on her new mission which is to find a girl that has been kidnapped by the slave traders. Shizuka is injured due to Maia's lack of concentration.
Millie and Tony Long save Maia from the slave traders. Tony confirms to Maia her recollection of being the only survivor of Elpida. The information branch of the Ocean Agency kidnaps Maia to insure she can say nothing about past events.
Tony tells the girls of Neriads about Maia's capture. As soon as Tsukasa returns from Greeland City, Shizuka recruits her to help them capture Maia from the Ocean Agency.
Tony lets Maia, Wong, Chang, and Lee use the attack sub so that they can find Elpida. Once inside, all of Maia's memories come back. She is able to find the time capsule she and her brother buried. Then she realizes the person who raised her as her Grandfather was really her older brother.
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