In its weird way the film affirms the human spirit and individuality ("the soul"), compared to the super-powered but stagnant and dying alien race that holds people captive here. Even though the hero is set up to think he's a Ripper-like murderer, he really isn't, and even villainous-seeming characters are secretly working toward the liberation of humanity.
Brief shots of bloody victims (female) of knife-killings, with spiral designs cut into flesh. Some of the zombie-like "strangers" get smashed/impaled, and one has the top of his head sheared off. Hypodermic needles plunged into foreheads.
Female nudity (topless and in profile) of a prostitute, bare-butt shot of the hero. Talk of an adulterous affair (which turns out not to have really happened).
Some cigarette smoking, social drinking as backdrop.