I see a lot of disappointed reviewers here that gave this film 1 or 2 stars. While it isn't a masterpiece I think the film does not deserve such a low rating.
I believe this may have to do with expectations: The Maus is listed under "horror" so people may expect either jump scares or cathartic violence and this film doesn't really offer either. It does offer a very personal nightmare ride that is rooted in the genocide of Bosnian Muslims perpetrated during the Yugoslavian civil war in the 1990s. If that is not something you know or care about then this may not be a movie for you. In particular, since it expects you to have a basic understanding of the conflict and does not do much explaining. Sadly, this probably is a factor that limits the film's audience to mainly Europeans.
The film is also not very verbose in spelling out everything that happens or explaining everything you see or hear. Even though gory visuals may arguably have been appropriate for the subject matter this film goes for subtlety and uses sound over visuals - leaving a lot to imagination. To me this was a good thing but it is also a potential limiting factor.
Contrary to other reviewers, I actually thought the writing of plot and characters was pretty plausible and relatable. It carries across very well the notion that the main character has endured things that her "innocent" foreign boyfriend cannot begin to comprehend and this is why she relates differently to the events in the story.
Overall, I found The Maus is not horror in the conventional sense but still a grim and unsettling experience. It is not without flaws and a few unnecessary, drawn out sequences but definitely a film worth giving a chance and, moreover, one that will make you think.
