I'd never heard of this, but I bought it anyway. I was googling people's favourite anime lists, looking for ideas, and Steins;Gate was on every list. "Oho," I thought and clicked 'buy'.
Is it as good as that suggests? Answer: yes, just about. It's not so world-shaking as to annihilate you with its brilliance and you'll be disappointed if you go in expecting something on that level, but it's intricate, funny, surprising and emotionally rich.
It's a time-travel story, which is interesting because this anime is based on a game. (The semi-colon in the title is because it's part of Nitroplus's Science Adventure visual novel series, between Chaos;Head and Robotics;Notes, by the way.) You know the grandfather paradox? What would happen if you tried to change your own history? Long-running time travel series can tie themselves in knots trying to work around those problems, but Steins;Gate dives headfirst into them and gets its hands dirtier than you've ever seen before. Changing history in this story is a game mechanic. It's what our heroes have to do, recursively. There's history-changing of history-changing. This is fascinating and I've never seen such a thorough treatment of the concept, helped considerably by the fact that they've thought about it ferociously and made everything make sense.
We don't always get full explanations, mind you, and the story mixes things up by including more than one theory of how history-changing works. I'm still not sure about the predestination, but I'm pretty sure it all hangs together if you give it some thought. On the rare occasions when I thought I'd spotted a plot hole, I soon realised that my criticism didn't stand up to the evidence (e.g. history had clearly changed at time W, rewriting X and so Y now knows Z) and the anime was consistently ahead of me. It also works hard to create scientifically plausible time travel, which blew me away in a genre that normally couldn't give two hoots about all that. Most importantly, though, it avoids the trap of "why should we care if anything can be unhappened?".
I will point out, though, that the show doesn't tidy up all its loose ends. I imagine some of those have come from the game, which can have multiple narrative paths and a fuller exploration of this fictional universe. I also don't mind not having every last detail nailed down. Nonetheless...
1. "My fork" and "my spoon" are funny, but we never learn why.
2. Daru's wife! Admittedly this one's huge enough that they address it in the 25th OVA episode, but it still counts as an example of a loose end because it's left hanging in the broadcast TV series, i.e. episodes 1-24.
3. That hallucination of Okarin in the time of the dinosaurs. (It's at the start of episode twelve.) Was it just a dream sequence or what? The easy answer would be "presumably just a dream sequence", but this is a show where we're being encouraged to study even the tiniest detail in laser-like precision, while in addition dream sequences are capable of being hangovers from alternate world-lines.
4. What happened to the momentary timeline where everyone disappeared? Mind you, here I have a feeling that the answer might be waiting in front of me if I'd just sit down and think it all out thoroughly enough.
The only thing I'd warn you about is that the characters aren't very likeable for the first half-dozen episodes. You'll need to plough through those. They're nerds, geeks and otaku. Together, they cover all the major mental and emotional handicaps you'd meet at a convention for fans of a major SF franchise. At the beginning, they're unsympathetic. They look delusional, bubbleheaded, perverted and so on, which is because they are. Their interactions together can be killingly funny, but it takes a fair while for us to peel back everyone's hard shell and learn to care about the people underneath. (Care we most certainly do, though.) They include:
OKABE, aka. OKARIN, aka. HOUOUIN KYOUMA - a gloating 18-year-old supervillain who calls himself a mad scientist and is plotting to take over the world. He also regularly has imaginary conversations with his mobile phone about how "the Organisation" is hunting him and is responsible for any setback in his daily life. Wears a lab coat. Hobbies: building a time machine, laughing maniacally.
MAYURI, aka. MAYUSHII - talks like an infant and has the technical expertise of a bowl of raspberry jelly. She's the queen of airheads and she understands about 20% of what everyone's saying. Hobbies: collecting toys, cosplay. The good news, though, is that she's adorable, cares about everyone and is actually the only member of Okabe's Future Gadget Laboratory who: (a) can read people, and (b) is normal enough that you could imagine her having had sex. (Well, there's also Faris, but she's not a core member.)
DARU, aka. HASHIDA - a fat computer geek whose sexual relationships involve two-dimensional partners. What he says to women often borders on sexual harassment. In fact he's quite funny, but he drove me up the wall anyway because I hated his voice actor. Tomokazu Seki is a big name, ironically, and Tomoko's a fan of his. He's famous for his versatility. I've heard a scene in which Tomokazu Seki playing all seven roles, including males and females with ages going from grandparents to children. He's been cast in female voice roles, including the lead in a lesbian romance. Now that's talent... but I still hate what he's doing as Daru, which sounds to me like an actor doing a silly comedy persona. I didn't believe in his line deliveries.
MAKISE KURISU - genius scientist with a personality like an ice wall. Much of the comedy comes from her interactions with the Future Gadget Laboratory members.
...and quite a few more. You'll get fond of them all. The most defective personality (and oft-seen in real life) is arguably that of Moeka Kiryu. who has such a strong attachment to text messages on her mobile phone that she does almost all her communication that way, even if you're standing in front of her and asking questions to her face.
Oh, and the OVA episode is more worthwhile than such things tend to be. The plot concluded in episode 24, of course, but episode 25 still justifies itself by addressing a couple of loose ends and showing us a happy ending for a particular relationship that had been left slightly up in the air by episodes 1-24.
I also admire the show's deftness. It's sure-footed in its transitions between weighty material and comedy. (Note the crisp, fast-paced comic timing of the voice actors in the latter, incidentally.)
This show is, above all, very clever. There's something clinical and precise about it, with the watchmaker-like storytelling that you'll find in all the most intricate time-twisting stories (e.g. Steven Moffat). However it also has emotional weight, as well as being often hilarious. It can flabbergast you. It's a show good enough to give as a Christmas or a birthday present, if you warn the recipient that it's not interested in being likeable towards the beginning. (Apart from anything else, it takes our heroes a while to develop a means of time travel, instead of just doing experiments on bananas. The plot gets more interesting once stuff's happening.)
I've seen claims that the game's a better experience than the anime. They'd be fundamentally different, obviously, even though the latter's a faithful adaptation of the main path through the former. An interactive game's obviously going to be more immersive and a more interesting fit with this story. However that doesn't mean the anime's not excellent. Recommended to anyone who can handle a bit of complexity... no, on second thoughts, to anyone.