It's a Japanese comedy film that's frequently annoying and/or stupid. However if you stick with it (not really recommended), it ends quite well.
It's about a gang of high school boys who love playing pranks. Their sleepy little town has a humourless, narrow-minded policeman, so naturally the two sides become enemies. It's war. This is basically a film of males being childish, over and over again. Imagine a blood feud, but fought with tricks like walking past the policeman's speed gun while wearing lots of metal, or hiding lots of S&M manga in the policeman's office and try to get him sacked. The best I can say of this is that it has funny moments.
The boys are also boys, so they're interested in girls. This is fairly tedious as well, but the female cast are actually far more entertaining and likeable than the males, because they're not idiots. Some of them are stunningly beautiful (e.g. Kumiko Aso), but my favourite was the tiny girl (Mika) who motivates the last-act Firework Heist.
She's in hospital and needs a heart operation, you see, but she wants to see a fireworks display. It's more complicated than that, obviously, but I wouldn't advise thinking about it too hard. You'd need to assume that a tiny girl who needs an operation can veto it, instead of having her parent(s) say, "You need this operation and you're having it." However she's adorable (and a more convincing actor than the adults), so you understand when our heroes want to do this for her. It has emotional weight. Thus I liked the film's last act a good deal more than I'd expected, despite regular outbreaks of nasty, toxic, disbelief-shattering overacting that's meant to be funny.
You see, this film has Japanese TV Disease. It thinks it's acceptable to wring outrageously broad performances out of actors who either don't care or aren't capable of making this work. It's really hard to be that big a ham and still give a performance that works, on at least some level. It's not impossible, mind you. There are people who are brilliant at it. However the Japanese film and TV industry is overflowing with actors who can't and keep having to prove it. This film is far from the worst offender, mind you. Mostly, it's okay. Easily 95% of it is watchable. Only specific little bits aren't fine. Most of this acting is perfectly acceptable and it's only the occasional nugget that'll put you off your food. It's not like swimming in shit. Instead it's more like being in your local swimming pool and having everything look clean and attractive, if you can ignore the turds regularly floating past.
I was wincing. That schoolboy dressed as a girl near the end and trying to act all burikko, squealing "ecchi", for instance. It breaks the film. I can't believe that I'm watching human beings and instead I just wish someone would fire that actor.
Apart from that, though, everyone's broadly fine. I was mildly fascinated by Hayato Ichihara as the pranksters' leader, who's pulling faces as if he thinks he's Jim Carrey. It's as if he's got facial Tourette's. It's wildly artificial... yet it works and Ichihara manages to be charming. On the other hand, I thought Kuranosuke Sasaki was all wrong as the cop. He's likeable enough that the character works and his choices are interesting, but he's not playing the character on the page. That cop's meant to be scary, mean, easily angered, etc. but Sasaki seems to have little interest in that. Visit the original blog and you'll see author's illustrations that show what Sasaki's failing to be.
Did I mention that this is based on a blog? Well, it is. There's a blog whose author is even now still using it to post this ongoing novel. That became a manga, which in turn became this movie. Apparently the original novel's pranksters have stricter rules about what pranks are out of bounds, which the movie ignores (and I didn't like the more mean-spirited pranks, like the over-waxed floor). Apparently the novel's half-autobiographical.
1. It's set in 1979, but it doesn't look as if it is. It has occasional songs and adverts from that era, while one or two of the cast are wearing clothes you wouldn't wear today. That's it.
2. I appreciated not getting a mushy finale of everyone making friends and learning to love each other. Everyone's managed to do a good thing for Mika, but that's not enough to stop morons being morons. It's a satisfying ending, with enough sharpness to feel honest.
3. This doesn't have an English-language DVD, as far as I know, but the Japanese DVD has English subtitles.
4. Minaka (Ellie Toyota) is introduced with the world's worst make-up.
5. I didn't really buy the biker gang flashback. Its story demands weight that this fluffy film can't give it.
Is this a good film? No. I hated the idiots (i.e. almost everyone) in the first half, while the worst of the acting could strip paint off walls. However I liked Mika and the film improves in the second half, until by the end I quite liked it. I think Sasaki's all wrong as the cop, but I also think that utter wrongness makes him a bit interesting. It's not irredemable, but its virtues aren't enough for me to recommend that you subject yourself to it.