I give credit to Andrea Bianchi (at first I thought it was a female director, the one lone one among the pack of the Giallo, but digging deeper Andrea is apparently a male name), for trying to put a couple of crazy twists: the killer looks like a cross between a dominatrix and a hardcore biker out of Mad Max, covered in total black leather with a big black helmet, there is a moment or two that do startle with the killer's presence. Indeed, the killer is for the most part much smarter than almost all of the cast, which can be fun to watch once or twice...
But the problem with Bianchi's direction is that past the excess nudity, which isn't a bad thing for a sleazy Italian horror flick, there's no suspense to his craft. While the cinematography is accomplished the actual direction as far as suspense goes is pretty weak. Suffice to say, Bianchi is no Argento. It's not a total loss, but it's also weakened by the really bad dubbing (Godzilla sometimes fares better), and some really ridiculous characters, like the fat guy that tries to have his way with the older blonde owner of the fashion studio, that aren't very funny.
It's got some hip 70s music, and a few memorable bits (mostly early on, with stuff that doesn't have to do even with the killer), but really this movie doesn't live up to the awesome potential of its title. The trailer on the Blue Underground DVD, on the other hand, is really amazing.