It's thoughtful and interesting. However it's also dry enough to be a bit of a slog if you try to marathon it. It's cold, dispassionate and somehow doesn't manage to get laughs even with material that's theoretically funny.
Its premise is that there are people who can stop time. There's a magic stone. Drip your blood on to it and you might become capable of freezing the universe. You'll still be able to walk around, breathe the air and even eat food, mind you. (Someone asks how this works and the answer is "you think I understand this stuff?") You can move inanimate objects, including "stalled" people, but they'll be petrified again afterwards.
Obviously this is begging to be misused. Steal whatever you want! Undress motionless women in the street! (Theoretically you could go beyond that, but fortunately the anime never goes there.) However there are dangers too. Firstly, don't provoke the Handlers. These look like upside-down flying tree roots, they're bigger than buildings and they'll crush your head if they don't like you. Trying to kill the "stalled" is the best way of attracting one.
After that, you'll want to look out for religious cultists who've been worshipping your family's time-freezing stone for generations and who are following murder instructions from their creepy boss, Sagawa. These include "no blood or semen".
This is one of those idea-driven shows that's basically a cross between murder chess and SF exploration. The frozen world's a pretty lonely place and there's no let-up while you're there. Don't get killed. Find out what's going on. Hunt the people who are hunting you. The baddies are grim, humourless and often kind of robotic. The goodies are a bit better than that, but not much. They're a dirty poor family of lowlifes and losers, with Juri being incapable of passing a job interview, her brother being a NEET who plays video games all day, Grandad being a gruff, secretive grump and Dad being a selfish unemployed slob who'll have delusions of grandeur and be the show's designated butt monkey. You can see immediately why Grandad kept the stone's existence secret from them.
Juri and Grandad are determined, tough and have a strong moral core, though. They're reasonably likeable. They keep things watchable, if you're not trying to do too many episodes back-to-back. Juri can even be fun, although she's also frighteningly clear-thinking.
Would I recommend this show? Probably not to a general audience, but it's a serious work of uncompromisingly hard SF. There's a lot of detail, integrity and intricate logic in the rules of this frozen world, its guardians and the powers you can either gain or have. I appreciated how deeply the show's thought about what it would be like to be trapped in a frozen instant of time. You wouldn't call this show fun, but that wasn't the aim. (It's not entirely without humour, though.) The ending could be said to include a deus ex machina, but personally I quite liked that as a surprising but logical extrapolation of the show's mythology.
I have a lot of respect for this show. I'm glad I saw it. However I can't see myself ever feeling the need to rewatch it and I deleted the episodes afterwards.