The All Night Long trilogy reaches its apotheosis with the third instalment: it is both the best realised and the most relentless of the lot. Though it has to be said that "best realised" is a relative statement.

Like its two predecessors, All Night Long 3 revolves around the descent of a nerdy teenager into a disturbed killer. His work environment certainly doesn't help matters. As a cleaner in a love hotel (where couples can rent rooms by the hour), he is surrounded by an equally warped group of colleagues who share a penchant for voyeurism and collecting pubic hairs.

From cleaning up dirty tissues and used condoms, young Kikuo develops a fascination for garbage, specifically the household garbage of women. On one of his nightly scavenger hunts, he encounters Kawasaki, who calls himself a 'dust hunter' and who takes the debutant under his wing. After meeting Kawasaki and seeing the rows of personal files he has meticulously put together from women's personal objects found in the trash (incorporating everything from addresses to menstrual cycles), Kikuo's own methods become more intensive and methodical. When three of his colleagues rape and abuse a girl they found stealing at the hotel, Kikuo takes her back home with him, chains her to the bed and starts to experimentally torture the helpless girl to extract as much data as possible for his files.

Despite all its philosophising about the worthlessness of human life and its rhetoric about human garbage, the All Night Long series would seem to be little more than smart exploitation of a nation's fear of the generation it doesn't understand. By playing off real-life phenomena such as bullying, world-weary otaku hermits and juvenile delinquency, the films represent the establishment's worst fears come to life: that underneath the façade of tranquil, regulated society, the younger generations are slowly and irrevocably deteriorating into anarchistic, violent sociopaths.

Matsumura exaggerates it to good effect, but by layering on the gore and shocks, by making leaps of credibility in his plotting and by his clumsy direction, he belies his true intentions. Surely someone with a serious point to make would strive to deliver that point in the most effective way possible, and not have it be obscured by elements that could have been easily avoided with a little bit more effort? Certainly All Night Long 3 is effective, but as a violent, gory exploitation movie. And while there's absolutely nothing wrong with that (it works very well this way, in fact) its cod-philosophy deserve to be taken with several shakers of salt.