Throughout the series, Kaiji finds himself entangled in several Yakuza schemes, such as the aforementioned cruise ship, trying to get out of a labour camp, and in the grand finale, winning $500 million from a pachinko machine that seems to have more defences than the Siegfried Line.
The style of Kaiji is very unique, and in a multitude of ways. The one that sticks out to most people I would say would be the art style, which is certainly unconventional. Some would call it ugly, but I myself would describe it as more just a bit different to what is standard - the rough edges do serve the series very well, and I think this is best emphasised by the physical appearances of the main antagonists, who all look very menacing, and almost demonic. The soundtrack of Kaiji is simply phenomenal, and I get the impression that whoever was responsible for it had worked on video game OSTs in the past - the tension in Kaiji is unlike anything I've ever seen before, and I think that the masterful, and highly varied, pieces that play throughout are largely the cause of this.
Kaiji is our main character, and he's certainly a very compelling one - seeing him get completely broken by the monstrous situations he's confronted with, and he is a man that is not well suited to it. Very emotional and prone to outbursts, and he seemed to end up crying in sadness almost once per episode. Still, his adversaries in the Yakuza should not take a sideline, and they seem to cover just about every main base you could expect for someone in there: a condescending man who likes to give long monologues, a man who just enjoys seeing people suffer, one who pretends to be friendly but is actually a massive Jew, and one with a God complex of sorts. I can't really do them justice with short descriptions like these, and any more would just spoil the excitement of the show.
All in all, Kaiji is an excellent show, with some of the best tension I think I've ever seen, and is absolutely solid. Some of the forced faux philosophical monologues aren't great, and admittedly the finale is far from grand, I really did not enjoy it as much as the previous ones, but these are minor setbacks on a great show. Spoilers in the paragraph following this one, so you've been warned.
I don't usually like to get into the "messages" behind shows, but I think I shall do so here. In the first episode, we see a poster that reads "The future is in our hands" on Kaiji's wall, and this is also the first line in the first season's OP. Just a minor message, it doesn't really mean much, and that's what I thought, up until the finale, wherein the OP started playing when Kaiji won the $500 million. As individuals, we may not be able to change the world, nor make things perfect, but for our own personal lives, we have great impact, based upon our decisions, and that's shown very clearly here. Kaiji wins the $500 million, most of which he sends to his friends in the camp, who helped him get there. It would have been all too easy for him to forget about them, and go live the good life, but he chooses not to, because he's a morally righteous man (and for the best, I wasn't especially interested in seeing his morals get corrupted by money, save that for shows wherein the protagonists are in the Yakuza themselves), and a large amount of it because he signed a contract for Endou with an extortionate interest rate, when he should've just read it first. He has just a couple thousand by the end of it, and shamefully admits he spent it all on pachinko, and this is just a testament to Kaiji's character. He never learns, he may get out of the hole he digs himself, but he falls back into another one. The future is in his hands, but is it safe in his hands? Not very. He was a NEET with no future by episode 1, and even though he won 500 million fucking dollars, by the episode 26, he had barely changed, the only difference is he probably got a mountain of mental health issues given what he had to go through.
