Within the Kanagawa prefecture lies the seaside city of Umineko. There, Kaname Okiura, a student in his 2nd year of high school, attends Umineko Shōgyō High School (海猫商業高等学校, Umineko Shōgyō Kōtō Gakkō, lit. Seacats Commerce High School), or Umisho for short. He is also the manager of the Umisho's swim team though he himself doesn't know how to swim. In fact, he is afraid of the water stemming from an incident which occurred some years ago. While he was at the beach, he had nearly drowned when a 'mermaid' pulled him under the water. He joined the school's swimming club in order to learn how to swim, but the club is filled with weirdos, who don't teach him swimming.
One day, a floating house arrives at the shores of Umisho bearing two persons. One of these is a cheerful, sunny, happy-go-lucky girl named Amuro Ninagawa, a transfer student to Umisho, and the other is her father. Her incredible swimming speed makes her an instant hit with the swimming club, but Okiura is surprised, as she reminds him of the mermaid he saw only once in his early childhood. After her floating house is destroyed during a storm she moves to Kaname's house.
The fictional island, where the series is set, is modeled on the real island of Enoshima in Fujisawa, Kanagawa.
Amuro Ninagawa (蜷川 あむろ, Ninagawa Amuro) Voiced by: Aki Toyosaki
Second year student, and a new transfer student from the Daito Islands, Okinawa at Umishō. Despite her being a dedicated and skilled swimmer, she finds difficulties in performing at competitions due to her not being used to the rules and environment of professional swimming (for instance, in her first attempt at swimming in a pool, she bumped her head on the pool's edge on the opposite end from where she started, and cried for some time from the headache, since she was used to swimming in the open ocean). Among her other uncommon habits, she prefers swimming nude, and has no shame of doing so, especially around Kaname.
Kaname Okiura (沖浦 要, Okiura Kaname) Voiced by: Toshiyuki Toyonaga
Second year student, and the swimming team's manager. He had a traumatic experience involving a creature he describes as a mermaid during his childhood, and after which he has been afraid of swimming ever since. However this scenario started to change after Amuro's arrival at Umishō. Always in trouble due to Amuro's unpredictable behavior, he usually denies his growing feelings for her.
Momoko Orizuka (織塚 桃子, Orizuka Momoko) Voiced by: Hitomi Nabatame
Third year student, and vice-captain of the swimming team. The most rational and serious character, she serves as the straight man of most characters and can't stand the antics of Ikariya.
Maki Ikuta (生田 蒔輝, Ikuta Maki) Voiced by: Ai Shimizu
A first year student, nicknamed Makio
(マキオ). Too small for her age, she is usually mistaken as a junior high student. Despite being a member of the swimming team, she is still learning how to properly swim by taking lessons from Kaname.
Masa Ikariya (碇矢 雅, Ikariya Masa) Voiced by: Makoto Yasumura
Team Captain, nicknamed Ikamasa. Third year, muscle-bound, and obsessed with shaving his and other people's body hair, and with wearing revealing Speedo bikini swim suits. He is, in fact, the most annoying character of the swim team, driving most of the characters crazy from his antics.
Mirei Shizuoka (静岡 みれい, Shizuoka Mirei) Voiced by: Yukari Fukui
A second year. Admired by the boys, she is very self-conscious when people stare at her. Her secret promiscuity is a recurring gag in the series: she wears skimpy lingerie under her clothes, she has a collection of kokeshis (Japanese dolls) in her bedroom and although she doesn't like people looking at her, she likes to look at members of the opposite sex or anything that resembles them (ie a giant statue or a large horn). It's revealed when Kaname goes to her house that apparently she got this sexual behavior from her parents, who often engage in sexual roleplay. She is a very skilled swimmer as she almost won the Kantou Tournament in 200 meters the year before the series starts. Her grandfather is the creator of the Shizu Group. She also has feelings for Kaname, however it is uncertain.
Maaya Nanako (魚々戸 真綾, Nanako Maaya) Voiced by: Sayuri Yahagi
First year student. A famous swimmer and model who transfers to Umishō in order to get close to Kaname, for whom she has had a crush since childhood. She considers Amuro as a rival and competes with her for Kaname's attention. She has a noticeable small fang and wears a swimsuit different from the rest of the team. Like Maki she has small breasts, and has a huge contempt for girls with big breasts like Amuro and Shizuka. She forms an "Alliance" with Maki to help make their breasts grow.
Sanae Kise (黄瀬 早苗, Kise Sayane) Voiced by: Ryōko Shintani
A third year student. A co-founder of Umisho's swimming club and Orizuka's childhood friend. Usually tends to bring trouble to those around her. She also makes up stories and lies just to tease others, and to also gain other guys attention.
Chigusa Yasu (安 千草, Yasu Chigusa) Voiced by: Yuka Iguchi
A first year.
Kaori Himekawa (姫川 佳織, Himekawa Kaori) Voiced by: Ayumi Murata
A second year, and one of the members of the swimming team.
Yamana Yoshizawa (吉澤 やまな, Yoshizawa Yamana) Voiced by: Yukiko Monden
A second year.
Asami Oyamada (小山田 麻美, Oyamada Asami) Voiced by: Ayahi Takagaki
A second year.
Keiko Nakamura (中村 恵子, Nakamura Keiko) Voiced by: Miki Ootani
A second year.
Yasuyo Nara (奈良 保代, Nara Yasuyo)
A second year.
Miku Nagira (凪良 みく, Nagira Miku) Voiced by: Hanami Hirai
A second year.
Akira Koshiba (小柴あきら, Koshiba Akira) Voiced by: Satomi Hanamura
A first year.
Takeda Seito (武田 聖斗, Seito Takeda) Voiced by: Satomi Kōrogi
A second year, and another pervert of the swimming club. Likes girls with big breasts, and out of almost all of the girls in the swimming club, he takes the most interest in Shizuka.
Tsunumi Isao (堤 勲, Isao Tsunumi) Voiced by: Jin Sakakibara
A second year.
Tobe Jun (戸部 純, Jun Tobe)
A first or second year, and another perverted member of the swimming club. He wears large glasses and is quite intelligent. His choice of swimsuit, like Ikuta, is a speedo(albeit more modest).
Iori
A manga only character. He is the personal trainer of Maaya and also happens to be a top model featured in weekly column in swimming magazine. He actually happened to only be Maaya's coach so that he could get close to Okiura, her childhood friend because he really wanted to be his coach. He actually has zero interest in girls and those is in truth he is a homosexual as he says this out loud in front of everyone.
Taku Ikariya
A manga only character. He is the younger brother of Masa and competes in the same tournament as his brother (even in the same events as him). He has also been said to look like his brother only cooler looking (he even is better at swimming and studying then his brother). He also happened to be on the same swimming team as Momoko and Masa in elementary and middle school. He seems to have a crush on Momoko and they seem to get along as well. He goes to Shogyo all-boys senior high school. He seems to have a rivalry with his brother for Momoko's attention.
First volume: released January 17, 2006, ISBN 4-06-363618-6
Second volume: released April 17, 2006, ISBN 4-06-363662-3
Third volume: released August 17, 2006, ISBN 4-06-363710-7
Fourth volume: released December 15, 2006, ISBN 4-06-363764-6
Fifth volume: released April 17, 2007, ISBN 978-4-06-363820-2
Sixth volume: released July 17, 2007, ISBN 978-4-06-363855-4
Seventh volume: released October 17, 2007, ISBN 978-4-06-363902-5
Eighth volume: released March 15, 2008, ISBN 978-4-06-363966-7
Ninth volume: released June 17, 2008, ISBN 978-4-06-362114-3
The series has been adapted into an anime television series, which premiered in Japan from July 3, 2007 on Chiba TV, Tokyo MX, and numerous other UHF television stations. Animated by Artland, it is being directed by Kōichirō Sōtome and written by Mamiko Ikeda.
Original Creator: Mitsuru Hattori
Planning: Hiroaki Morita, Yoshirō Kataoka
Series Composition: Mamiko Ikeda
Character Design and Chief Animation Director: Rie Nishino
Art Director: Chikako Shibata
Color Designs: Tomoko Yamazaki
Photography Director: Satoshi Fujita
Editing: Hiromasa Mastumura
Sound Director: Kazuya Tanaka
Music: Yasumasa Satō
Music Producers: Michiko Koyanagi
Music Production: 5pb.
Sound Effects: Noriko Izumo (Suwara Production)
Sound Studio: Delfi Sound, Seion Studio
Sound Production: DAX Production
Promotion: Tomoko Hasegawa, Teruhiko Satō, Katsunori Takahashi, Yuri Koya
Associate Producers: Noriko Doi, Tetsuko Otani
Producers: Bunpei Ogawa, Hiroyuki Ōmori
Executive Producer: Hidenobu Watanabe
Director: Kōichirō Sōtome
Animation Production: Artland
Production: Umishō Production Committee (Geneon Entertainment, Marvelous Entertainment, 5pb., Pony Canyon Enterprise)
Opening theme: "Dolphin☆Jet"
Lyrics and composition: Chiyomaru Shikura, arrangement: Kōji Ueno, performance: Ayane
Ending theme: "Splash Blue ~ Sun and Lemonade" (Splash BLUE〜太陽とレモネード, Splash BLUE ~ Taiyō to Remonēdo)
Lyrics and composition: Urara Takai, arrangement: Kōji Ueno, performance: Ayumi Murata
An internet radio version of the anime series, Kenkō Zenrakei Suieibu Umishō: Junbi Undō (ケンコー全裸系水泳部 ウミショー 準備運動), was first streamed on the Japanese websites Ōnsen and BEWE from May 16, 2007 and June 27, 2007. A continuation, Kenkō Zenrakei Suieibu Umishō: Natsu!! Honban (ケンコー全裸系水泳部 ウミショー 夏!!本番), began streaming on July 4, 2007. The first version of the series featured Hitomi Nabatame, voice actor of Momoko Orizuka, while the continuation featured Nabatame and Aki Toyosaki, voice actor of Amuro Ninagawa.
5pb inc. published an Umisho game on PlayStation 2, under the 5gk. (The Five Games and Kid) title.
