This is probably the fastest-paced and most action-packed of the German Edgar Wallace "krimi" series, a cross between the Dr. Mabuse films of yore and 60's pop thrillers like Batman and the Man from UNCLE. It reintroduces the outrageous villain from an earlier film who dons a stylish monk's habit and breaks the necks of victims with the curl of a deadly whip. Set at a posh girls' school filled with lecherous middle-aged professors, and with the cops fondling their hot-to-trot secretaries at every opportunity, it certainly is a throwback to those wonderfully politically-incorrect times. There's a definite link to a later Wallace-based film, the excellent giallo "Whatever Happened to Solange?", which also concerns female students being corrupted by (and corrupting?) their elders. Quite appropriate to the monk theme, the master-mind villain uses booby-trapped bibles here to deal some of the death blows, and also maintains a reptile-replete dungeon to amuse his captive audiences.
Alfred Vohrer was always the most playful and visually flamboyant of the series directors, and here the lurid colour cinematography is the real star of the show. The Monk appears in a raving scarlet cowl and robe, tastefully setting off the lustrous white whip, while appearing against purplish-night backgrounds. There's also a voyeur-friendly turquoise swimming pool which looks great both as a glowing milieu for the nubile students and as a shadowy backdrop for one of the murder scenes. The trademark "kicker" of hiding the "Ende" card somewhere in the set of the last scene is also quite memorable here. And there's a fine brassy and twangy score for retro-music fans.
Fans of the series will definitely miss the flippant Eddie Arent character in these later films. Instead, the chief inspector Sir John takes on the role of buffoon, convinced that he has mastered criminal psychology after taking a few night courses. Unfortunately, Klaus Kinski had also gone on to bigger and better things. The krimis had lost some of their offbeat subversive charm by this point, and now worked on a much more blatant pop-culture level, which will make this one quite accessible to uninitiated viewers.

I really, really wanted to like Julian Po. I think that Slater is underrated as an actor, and that many of the supporting players here are better than they are given a chance to demonstrate in this film. I realize this is based on a short story which I have not read. So, I do not know if what I see as the film's faults originated with the story, or were imposed on it by the director/screenwriter. The premise is wonderful, and I loved the voiceover, confessional tone the opening narration strikes. But then...? Nothing! Several of the cliched local characters ask Julian pointblank to explain his intention to commit suicide. One could argue that he doesn't answer, because it's none of their business. But Julian is the one who, under only token pressure, blurted out his intentions in public. Then neither Julian nor the director/writer, despite the fact that the Julian character is keeping a tape recorded journal for God's sake, seem inclined to provide anything beyond the scant initial information on Julian's life. He says he was a bookkeeper. He says his family moved around when he was a child, due to his father's job. So what? There are several interactions with the locals which seem designed to illuminate Julian's purpose. But none of them go anywhere, because Julian seems to regard all these dopey locals as if they were aliens from another planet, as if he were the ultimate (and only) sane one among them. This might work as an allegory, if Julian Po had any defining characteristics or anything approaching wisdom to impart. The closest he comes to revealing anything about himself is in the scene in which he purposely humiliates the naive, religious wife of the mechanic. And what this scene reveals is not anything that would inspire empathy for Julian. I can only see the Julian character --as rendered--as selfish, petty, and totally condescending. Sort of matches the attitude of the director of this half-baked, contrived film. And poor Michael Parks, an actor who once had so much promise, is given nothing to work with here.