Not bad except for the 'Celebration' and accents
I found this movie to be entertaining, with an appropriately dark tone, decent acting, interesting set, and a nice mystery.
The two things that really hurt it, however were the modern(ish) festival/celebration scene and the accents.
The festival was so dumb it almost made me laugh. (Post-)Modern music and dancing and comepletely anachronistic elements like a Victoria's Secret (type) Super Model posing in the middle and not moving. This entire scene really sucked.
The other thing was the accents and modern vernacular. It litterally sounded like it was shot on the street of any current American city. The only person who had any "setting-appropriate" accent was Gary Oldman's character. For some reason, he had the only "old European accent" that one might expect in a period piece like this, and not surprisingly, was the only character who seemed to fit in a setting/story like this.