About every decade or so, I find it necessary to remind myself why I think Jess Franco is over-rated, and basically a talentless hack of a director who demonstrates skill only by accident [hey, if I made 200 movies, a couple wouldn't suck, by sheer chance]. This, described on another site as "the director's finest hour", sent me to sleep inside twenty minutes, probably as a defence mechanism against what may be the most hideous smooth jazz soundtrack ever used - if I had to listen to it in an elevator, I get out and use the stairs, but it's especially inappropriate for a film about a widow out to murder those she holds responsible for her husband's suicide. It starts with a bizarre subplot about how he's performing questionable medical experiments, but this angle seems rapidly to be entirely forgotten.
In other hands, this might have been an interesting premise, but Franco screws it up, managing to make murder dull - which I guess is something of an achievement. We get one lengthy sequence after another of Mrs. Johnson luring and killing her victims, without any development in story or character beyond the first 20 minutes. Meanwhile, the director indulges his usual technique of ending scenes by zooming in to something entirely irrelevant (a lamp-shade, a mountain, etc.); like the movie in general, this badly overstays its welcome. I do admit Miranda has potential, sadly ended by a car-crash death later in 1970: Ecstasy was her last film, and despite her presence and intensity, it's definitely not something I'd want as my memorial.