There is a steadily growing sub-genre of the post-Apocalyptic film centered around groups of survivors hiding in a shelter together. One could point at A Quiet Place as one of the more successful examples although it isn’t quite as confined as most of them (or perhaps one might say that the family’s confinement isn’t purely physical).
Here we have a family in hiding from the mysterious and unseen Breathers: they’ve managed to find a precarious existence for themselves in a former air raid shelter and have survived there for almost a year. But their supplies are getting low, a rat found its way into their food supply, smoke from an accidental fire may have given away their location, and one of the Breathers is outside.
It’s reasonably tense, there are quite a few good moments and it comes with a few twists at the end as the situation isn’t quite what we think it is. It isn’t exactly outstanding, but is still quite entertaining in a modest sort of way.
The most interesting thing about it, though, is that it was written and directed by The Duffer Brothers (Matt and Ross Duffer), who have since gone on to greater fame with Stranger Things. I still haven’t caught up with that one, so I can’t really comment on that, but it doesn’t hark back to the great SF films of the Eighties as their series does.
But then we should know better than to expect any creator to do the same thing all the time. It just doesn’t work that way — and besides, it would get boring before long.
However, there is one thing I do have to say about this one: if a creature can smell food through a steel can, then chew its way unnoticed through it, that must be one hell of a rat!