An uncanny plot and claustrophobic little sets make this odd but fast-paced story play out in very unexpected ways. Initially, the science lab setting gives it a sci-fi air - later it feels more like a thriller or a mystery - other times a Brazilian soap opera; but somehow the tonal shifts work in a sort of Freudian whirly-gig fashion and we drift from one to the other seamlessly. I can see why this movie enjoys cult status - it has its camp aspects - but there is also some artistic merit in a couple of memorable shots and in its unsettling eerie atmosphere. Notable for its femme fatale vs femme fatale conflicts, this will certainly make you sit up and watch for 68 mins. Although Hillary Brooke and Ruth Ford played their roles perfectly well, I was especially taken by Brenda Marshall, who sadly did make many more movies. A potent little brew of intrigue, twisted passions, and...strangeness. I heartily recommend for lovers of noir or 'otherwise'.