As a giallo this movie is a real disappointment. The plot is virtually non-existent, the suspense is nil, aside from the widescreen compositions the cinematography is unimpressive, and I'm sure the occasionally interesting score was recycled from a better movie. Klaus Kinski obviously phoned in his performance (long-distance with a very bad connection) and Rosalba Neri (aka Sarah Bay) is pretty much wasted.
On the other hand, if you're looking for softcore porn, this movie is a relative masterpiece. The crisp cinematography is superior to just about anything else in that genre, and you have an elegant Italian instrumental score as opposed to the usual, grating wah-wah synthesizer. The plot may be anemic, but it certainly doesn't interfere with any of the action. Even sleepwalking through their respective roles, Neri and Kinski can act circles around your typical softcore sex performer. Kinski, of course, does not actually perform any sex scenes (which is good--we're talking Klaus here, not Natassia). Neri, on the other hand, has done many sex scenes in much better movies, but I'm confident no one will complain about her scenes here, even if they don't exactly show off her considerable acting talent. As in many European movies, Neri's "solo" sex scene really pushes the line between softcore and hardcore, but in the best possible way. Only the ending is terrible regardless. It comes out of nowhere and will appeal only to fans of medieval weaponry and/or the Richard Speck student nurse murders.