2008, Ryûhei Kitamura (japanese director of Versus and Azumi) -- Netflix
Bradley Cooper plays the obsessed guy very well. At first he is disturbed by his role as photographer of the violent moment. He is not sure about where it will take him. But it is much further than just following thugs into the subway to see who they will assault. Connect a few dots and suddenly he realizes that there is something else up with the well dressed butcher with the doctor's bag. Vinnie Jones is basically playing himself, the recognizably controlled scary guy with a grim visage. And that is it, that is the crux of the movie, the interaction between the photographer and the murderer.
Vinnie's butcher does nasty nasty work. He has a massively heavy hammer and a sharp carving knife. He has a grim determination to do his required work quickly. He obviously has little concern for his victims. That Bradley's photographer is able to set aside his concern for people in order to catch the perfect shot, shows a similar determination. It's only a matter of time before the two paths sync up. It's mystical but not completely explained.
Kitamura really plays up the gore, going beyond the knife hacking and hammer smashing. Eyes get knocked out of heads and heads even knocked off their stumps. The view through the latter victim's eyes as she gazes on her own body is eerie. By the time we get to the butchering of humans, we are immune to the blood. At least we don't have to smell it.
But what are the motivations of all of this? Like in the original short story, they are never really explained. So what if we have ghouls living under the city? So what if there are determined roles in serving those ghouls, so the outside world doesn't have to know? Unless these humanoid flesh eaters serve an even more horrible master, then there is no reason humans wouldn't just hunt them down and kill them. There should be no reason for a small conspiracy that has been killing for as long as there have been subways. We never really get any resolution, just the transition from Vinnie to Bradley, which was seen a mile away, at the beginning of the movie.