Certainly we are not talking about a fresh concept, but the way this movie has been done is refreshing. By viewing it while being still in the middle of COVID-19 pandemic, some things seem like being written by someone who can foresee future.
The movie keeps its tension all over its duration, though slowing a bit after middle, but then rising again in the end.
Being italian myself, let me mention the performance by the actors: i hate most of italian actors because they are so dramatic, so overreacting. I have to say that 90% of the movie is acted by people who look, act and speak as regular people, and the dialogues are very realistic. I hope that translations have kept this feature intact.
Sound and music are also very good.
Some scenes suddenly shift the movie from a documentaristic point of view to a cinematic one, and this is of course weird, but all in all, also considering the clearly low budget available, this movie is simply great.