13 Dolls in Darkness stands alone in the world of horror films because of its unique take on the genre tropes of 70s giallos and 80s slashers. It is shot in the style of German expressionist silent film, complete with title cards in lieu of recorded dialogue.
The film will be challenging to some viewers in the same way that watching (real) old silent films can be challenging: the contrasty, flickering images can be a bit washed out (in this case, intentionally), and the lack of dialogue and diegetic sound make it difficult to follow unless you are paying close attention -- in other words, you can't put this thing on as background noise -- it demands attention. In the case of this film, I'd say the attention is warranted. The camera angles and composition are compelling and the story, while intentionally trope-heavy, is interesting if you are a giallo fan.
It's pretty fun to see these tropes and actual gore played out as if it were shot in the early 20th century. The only differences between this film and a 20s era film are the use of some pre-recorded sound effects (church bells, trains, door creaks, etc -- not unlike what you may have heard in an old radio show from that era), and much of the music has a more modern "sound-design" feel -- more typical of modern horror than anything from the silent film era. That might be one of my few criticisms of this film: I found myself wishing for a melodramatic piano score, more in line with what you would associate with silent film. Additionally, I would have liked to have seen this done in period costumes as opposed to some of the more modern costume choices, but I'm assuming Müller was being intentionally anachronistic.
Müller is a new filmmaker and certainly one to watch. I'd love to see what she could do with a real budget. 13 Dolls in Darkness is worth your time if you are a fan of giallos and slashers, but have no interest in watching your one-millionth no-budget Friday the 13th clone. This film is truly something unique and, while possibly challenging for some viewers, is a perfect example of how clever ideas always trump inflated budgets.