Kou Ichinomiya, heir to the prestigious Ichinomiya Company has only one mission in life: to not owe a favor to anyone. He's lived that way for 21 years. Until one day when, his pants hung up on top of a bridge, he ends up falling, with the bridge pillar, into the river down below. Nino, a girl who lives under the bridge, saves his life. Kou wants to pay her back, but Nino desires nothing except for a boyfriend; so Kou winds up living in strange community under the bridge with Nino, who also claims to be from Venus, now under the name of Recruit ("Ric" for short).Originally a manga by Hikaru Nakamura, published by Square Enix, had an anime adaptation aired in the spring of 2010, animated by Studio Shaft. It was followed up by a second season, Arakawa Under the Bridge x Bridge (or Arakawa Under the Bridge x 2), that aired in the fall of that year.There was also a TV Drama adaptation followed up by a movie in 2011 and 2012, which starred Kento Hayashi as Kou, Mirei Kiritani as Nino and another bunch of familiar actors of the medium (Shun Oguri, Yuu Shirota, Takayuki Yamada, etc).Not to be confused with Hiromu Arakawa, creator of Fullmetal Alchemist, who presumably doesn't live under a bridge, though she may live in a nearby field...
Art Shift: The fifth episode's opening. Even without the apparent rotoscoping, the art has a rather different look.
And every once in a while, Ric shifts into a very shoujo manga look. For example, when he's imagining being Nino's bride (yes, not the other way around), or when he's under "Kameari syndrome" — along with Hoshi and Last Samurai.
Author Avatar: From the manner that Nakamura draws herself, Kappa looks quite like her. To this manner, it was lampshaded that Kappa perceived her as a long-lost family member.
Authority Equals Asskicking: Hilariously averted in the case of Mayor, who is highly respected among the riverbank's society with Riku only pointing out he hasn't got any qualifications for this. Also played straight with Sister and invoked by Stella.
Maria's inability to snark at the guys causes her to snap on poor P-Ko in Episode 7 of Season 2.
Technically every single time that Sister's tongue slips into remembering his times as a militar more specifically when he remembers his affair with certain former spy... he gets attacked by scissors. Just saying.
Be Yourself: The bridge dwellers seem to center their lives around this rule.
Bitch in Sheep's Clothing: Maria, bonus points for keeping actual sheep in her farm. She doesn't bother too much with hiding it, though, as her looks and warm smile work at people who should know better...
Brainwashed: Kou throughout most of episode 8. Maybe those "tengu" aren't just weird guys in masks.
Shimazaki. Sometime after finding out Shiro was an already married man, and felt 'tricked', she was an easy target for an organization that plans to get into the deep of the whole deal about Nino and the secrets of the Arakawa River's villagers. Just because of her unhapiness and broken heart...
Breaking the Fourth Wall: There's a moment where Nino in the manga mentions about 'some people appear on the volume covers and other don't'... even glaring at the reader. Of course, Kou doesn't take it very well... (he is the only main character of the series that hasn't appeared in any of the (as of March 2013) covers of the manga... to his dismiss).
Once when Nino says that Kou 'wants to be with her forever', in parenthesis it's read '(So I would not forget him)'... which he pretty notes so much.
Maybe because Captain is just turning every plot of their lives as a manga, he is self aware that their lives and world (aka the manga itself) it's like '80% Comedy', and when 'time suddenly moves on, the plot thickens (all the subplot around Nino going to Venus), the final chapter is close (that is, if everything ends up right)... however... if you are already reading this right now, and are aware that the 13th volume has been recently released... oops.
Butt Monkey: Most of the characters get their share, but Kou as the outsider of the riverbank society and (deliberately) Only Sane Man gets the prize.
P-ko becomes the unfortunate target of Maria's wrath.
Cool Big Sis: Maria, bordering even at Onee-sama territory, although exclusively for the girls and children. The male part of the riverbank society usually receives a solid portion of bitchiness hidden behind a beautiful smile.
Cross Counter: Between the Mayor and P-ko of all people in Episode 12 of Season 2.
A Day in the Limelight: Last Samurai, Billy and Jacqueline, the only members of the bridge who the audience had not seen at all, get some screentime in the final episode of the first season. Lampshaded, of course.
Debt Detester: Kou has always lived by this principle, paying all debts as quickly as possible, but he finds himself in a quandry when a crazy woman (or not) who lives under a bridge saves his life.
Feed the Mole: From the looks at it, if the Mayor claims to be who he really is outside the riverbed, he already knew that Shimazaki was going to keep her game of spying on them, so there goes the full 'trust' issues he had on her... then again, if the spying devices were so obvious as pointed below, he knew the villagers are cloudcuckoolanders so, part of their claims were fishy enough to not look them up...
But then it leaves a lot of questions about the Captain's sci-fi manga, until the moment it was starting to be completely coinciding with what happened in real life about Nino, her close-to-be return to Venus, and Arakawa's riverbank to be something else...
Generation Xerox: Ric's dad gets his trousers stolen on top of the bridge, and refuses Nino's help. This time, however, Nino has already retrieved the trousers with her fishing pole, forcing Ric's dad to walk off without them just to avoid a debt.
Incredibly Obvious Bug: Do EVEN the villagers of the riverbed REALIZED that Shimazaki was spying on them? Or, well, do they even know the consequences of it? Because there's no WAY that those camera on Nino's room were TOO obvious too them to notice... but then again... it was planned to do so if someone knew Shimazaki was the mole after all.
In the Blood: Kou picked up most of his habits from his father. Whenever his father did something for him, he would always make him pay it back.
Jerkass: Hoshi acts like rather petty and visibly ineffectual Jerk Jock from high school and Rival-wannabe towards Riku.
Maria, though she's more of a sadist.
Limited Wardrobe: Nino's jersey, well, under the bridge Hoshi seems to be the only one changing his clothes regularly. Although Sister, Kappa and Riku's cases can be justified, and Ric apparently owns plenty of identical clothing.
And then again, they wash their clothes, too.
Line-of-Sight Name — How the kappa names people. For example, "Nino-san" comes from the 2-3 on the tag of her track outfit (2 is ni, the dash is no, 3 is san).
Live-Action Adaptation: It received a drama series and a follow-up movie that were released in 2011 and 2012, respectively.
Maintain The Lie: Kou has told representatives from his company that he's set up a power generator under the bridge and started a new company around it. The problem begins when the representatives come to check on him.
A Man Is Not a Virgin: Well, Kou is. Probably has something to do with his 'I won't owe anything to anyone' obsession...
Masculine Girl, Feminine Boy: When it comes to romance, Kou and Nino to some extent, as she is The Stoic and he has a bit of a shoujo heroine's heart. In chapter 162/episode 7, Kou has an Imagine Spot with Nino wearing a tuxedo and himself wearing a bridal dress, wondering how it got to that point.
Medium Blending: Every On the Next (and the first preview of the series) has a live-action man in a kappa suit, and, as of Season 2, a man with a star for a head.
Moment Killer: Various, but Hoshi is considered one of the main ones, even involuntarily, just as when he recorded in those dear tapes of Nino (and a bit of revelation about her past) with his errr, 'new song'.
Nun Too Holy: Sister, a man in a nun's habit with a large scar who holds Mass at gunpoint. Actually acts pretty close to a nun too, save for the idiosyncrasies.
Only Sane Man: Kou plays this role in the series. However, he can't really be considered "sane" if you consider how far he'll go to avoid debts.
Out of Focus: Although the concept of the series is based around Kou and Nino (they even get actor credits in the opening, which is extremely rare in anime), after the first couple of episodes in the anime, Nino shows up no more often than any of the minor characters. This seems to be just to remind the audience that she exists.
Pair the Spares: Played straight (albeit a bit bizarrely) with Hoshi and Amazoness.
Rescue Arc: At the moment where Ric and the other Arakawa villagers find out that Shimazaki was brainwashed, Billy decides to help to get her back. That is, he and his comrades become severely torturated until Captain helps them out.
Rule of Funny: Pretty much how the entire series runs, because at the end, it's also a gag manga series.
Samurai: Last Samurai, obviously. He's also a hair stylist.
Skepticism Failure: Inverted, at their first meeting, Kou believes, at least for a few minutes, that the man in the green suit is indeed a Kappa.
He comes up with the idea of Hoshi being a star-shaped monster feeding itself with heads of young men to posses their corpses and control it, rather than him being a young man himself and wearing a mask. Arakawa Riverbank's logic sank into him indeed.
Sister apparently owes some thanks for his knife skills to an old snake.
From his commentary during P-ko and the Mayor's fight, apparently both Ric and the Mayor are fans of Ashita no Joe.
When Amazoness displays the box containing "treasure" in the second episode of season two, Kou wonders if there's any O-Parts inside.
Also from the same episode, Amazoness says "And doesn't this makeup make me look like Avril?"
There's also a TheMoomins reference involving P-ko.
The title itself it's a reference to 'Under the Bridge', of Red Hot Chili Peppers, from whom Nakamura is a fan of (even the clothes of Hoshi are sometimes influenced by the fashion sense of the band during that time the song was released). Maybe the title is much more of a Meaningful Name too.
'Venus to Jesus'... could it be a shout out to Saint Young Men (also by Hikaru Nakamura), too?
Souvenir Land: Never trust the Arakawa bridge community to build a theme park.
No wonder that it could have been something that it was preserved from the beginning, since the original Takai was... a woman.
Super OCD: Shiro/Whitey is obsessed with standing on white lines to the point where he actually lugs around a portable line-maker wherever he goes. It is unknown what happens when he is taken off a white line, but during the Arakawa sumo tournament mini-arc both Sister and Maria withdrew from the finals because they did not want to find out.
Team Dad: Surprisingly, the Mayor can show his wise side from time to time.
That Came Out Wrong: Lampshaded in the marathon episode. Shiro races out way ahead only to turn back because he's run out of white powder. Kou warns him that he shouldn't say that out loud in case a policeman hears him.
"Well Done, Son" Guy: Kou's motivation since his childhood. There's also Kou's secretary, who yearns for Kou to call him father. Kou's real father does not approve ("Papa is still a father, after all"), especially after seeing that body pillow.