It's a trip. Imagine a combination of Battle Royale and Enid Blyton's Famous Five, with the gloating supervillain being a talking teddy bear. The animation's stylised to the point of deliberate absurdity, with pink blood and some gloriously unrealistic character designs. (Even I struggled with Genocider Sho's permanently protruding snake-like tongue, though, which must measure a good thirty centimetres.)
It's the most entertaining thing I've watched recently and I'm looking forward to the sequels. It's also a good anime based on a video game series. Unfortunately it's also hard to discuss without spoilers, but...
Fifteen lucky students get chosen by lottery to attend the elite high school, Hope's Peak Academy. That's what they're told, anyway. In fact, almost everything there is a lie. Firstly, Hope's Peak Academy isn't a school, because it has no teachers and no classes. The students never study anything and don't even seem to have access to educational materials.
Secondly, the students are the opposite of "lucky". They're going into a deathmatch organised by Monokuma, a sadistic Two-Face teddy bear who throws tantrums if no one's been killed recently. He has cameras all over the school to monitor the students, check for rule-breaking and identify all murderers for later judgement. Everyone's stuck in the school and the only way out is to commit murder and get all your friends killed. The rules of the game are:
1. If a corpse is found, everyone is notified and there's an investigation period.
2. After that comes a trial. Everyone has a chance to state their arguments, then there's a vote on who people think the killer is.
3. If the majority vote is correct, then the killer is executed. However if the majority gets it wrong, then the killer goes free and everyone else gets executed. These executions are luridly stylised even compared with the rest of the show, incidentally. I was wondering (incorrectly) if Studio Shaft did the animation.
This is a nifty format, I think. It's more unpredictable than Battle Royale and similar stories, since you can't immediately divide the cast into "sole survivor(s)" and "waiting for them to die". It's also taking the killings more seriously. It's not just a splatter spree. The cast are basically normal and every murder is given proper emotion, psychology and motivation. Deaths get investigated in proper whodunnit style, with surprisingly intricate chains of reasoning in the trial scenes. It's a format that invites you to don your thinking cap. Theoretically the show would break if any trial ever had only two participants, since there would be no mystery about the killer's identity and the vote would be a deadlock. However I suppose the answer would be to ensure things never reached that stage. You'd just murder everyone. If the game's gone on so long that there are only two or three survivors, they must be fearsome detectives to have cracked every single murder and you wouldn't fancy your chances of killing someone and then successfully bluffing your way through the investigation.
The show's relatively light-hearted, though. Dark, but entertainingly dark. You could tell some ghastly Danganronpa stories to make the audience open their wrists, but the show never goes there. Imagine, for instance, accidentally killing your would-be killer in self-defence. You'd have done nothing bad, but that wouldn't fly with Monokuma and your only options would be either to get all your friends executed or to get executed yourself. That would have been brutal, but there's nothing like that in the show. (There nearly was, though. An early version of the game was more serious, with a Saw-like vibe and in monochrome.) However these deaths are almost jolly, with censor-friendly pink blood and wacky executions.
It's unpredictable. I never guessed the next victim's identity. After that, the last few episodes change the rules and overturn our expectations. Ep.13 in particular goes mental, in ways that might disconcert viewers who'd been enjoying the show as a comfortable murder romp. The show had always made it clear from the beginning that it was about despair vs. hope (e.g. the school's name), but ep.13 takes that in new directions. I'm not sure what I think about ep.13, but I'll definitely be watching the 2016 sequels to get more story and more context. If those hadn't existed, my feelings about the finale might have been more complicated. I wouldn't call that a downer ending, but it's certainly not rainbows and butterflies either.
The cast are lively. The outrageous character designs (hair big enough to eat children, etc.) make them more immediately vivid, but they're also interesting in their own right. It's a big cast, but you feel you know everyone immediately, no one's just making up the numbers and you're never left wondering if you might have muddled up A and B.
It's different. It's cool. It has an attention-grabbing premise, but also the confidence to throw away its own formula. Its villain is a killer teddy bear with the voice of Doraemon, i.e. Nobuyo Oyama. It's silly and unrealistic, of course, but I wouldn't want it any other way.