What could be an intriguing variation on A Nightmare on Elm Street and Suicide Club, instead is murky in its character drama and underwhelming in horror. Characters are two-dimensionally developed and uninteresting, while the horror scenes are blandly integrated into the real world, and get repetitive in their fright tactics. The film also stretches out scenes much longer than it should, making it a rather dull.
Without getting into a philosophical digression that could not help but overstep the word-count limit, I want to assert that Nightmare Detective, while a reductive film about dream, is the greatest film of all time about the simultaneous pull toward and away from suicide, as well as about the kind of predatory sexuality the Japanese get so well. Shinya's casting of himself in Snake of June and here: best thing ever.
This was a really good movie, but like others have noted it does feel like the pilot to a television series. The last act of the movie shows Tsukamoto's cinematic prowess at the fullest. That scene where the horror is interrupted by abstract images and happy childhood days is beautiful and emotional; the sign of a director who knows what he's doing. I want to see more Tsukamoto, but one of his masterpieces next time.
Although this felt much more like a prologue to a story more than a complete film, it had many moments of eerie, nightmarish imagery. The way the "0" character moved and attacked within the dream world was the most effective aspect of the horror, otherwise it was kind of nonsensical and at times used bizarre funhouse-sounding techno music.