I'm a big fan of the second and third entries in the ALL NIGHT LONG series - personally I found the first "episode", though suitable "dark", is also relatively dull until the end. ALL NIGHT LONG: R, the fourth entry in the series is decent, but lacks some of the dark nihilism that makes some of the other entries so strong. My copy is Japanese with no English subs/dubs, so I'm sure I missed a bit of the plot-points, but I think I caught most of it...This one is about a nerdy kid who has a fascination with weird "experiments". He's also obsessed with a web-cam girl and decides to translate some of his experiments to her - this obviously doesn't work out too good for web-cam-girl. After the nerd "finishes" web-cam-girl off, he kidnaps another girl and does some more experimenting - this doesn't go so well either...There are a few decent gore scenes in R...but this entry in the series also doesn't feel as dark and sinister as ATROCITY or THE FINAL CHAPTER, so I didn't dig this one quite as much either. A few strong scenes but it drags at points when they could have been showing more "good stuff" - worth a look to fans of the series or J-splatter fans...7/10

"All Night Long R" was released on DVD only in Japan,but I managed to track it down.The film is not as savagely violent as the previous two movies "All Night Long 2" and "All Night Long 3",but the tone of it is definitely disturbing and depressing.It tells us about obviously disturbed Japanese individual named Yuuki who captures two Japanese girls.One of them, Reika,is brutally murdered and her captor cuts her up and takes her body parts like ears and breast.The second girl is chained to his bed and he performs a hideous experiments on her body."All Night Long R" is a rather slow-moving horror film that offers plenty of shocking violence.The acting is excellent and the killing of a Japanese boy is extremely vicious and cruel.Sometimes the film has a mood of a very sad romance.So if you're a fan of Katsuya Matsumura's works give this gem a look.