Someone, or some thing, is running amok in South Africa killing people. Okay, actually, it's someone- a man, not a demon at all, making the title a bit disappointing. In the opening, he kidnaps a young teenage girl and ties up her mother. He soon after kills a fellow who picks him up while hitchiking before babbling about how his mother thinks he's gay for his love of acting- shutting the guy up probably qualifies as a mercy killing.
Meanwhile, the family hires Cameron Mitchell, playing "just a man with ESP" to find the killer. When he gets to her room, he hears the sound of screaming angels, something that happens to me in the bedrooms of teenaged girls as well, and which clearly means something important. He soon realizes that what they're dealing with is "less than a man. But also more than a man. Much more." So a woman?
Turns out the killer is also stalking a young teacher and her visiting American friend who like to hang around the house and meditate. The young friend is dating a rich fellow who has won her heart by taking her out for lobster thermidor and wine. But the teacher friend doesn't seem compelled to inform her roomate that there's someone making scary phone calls and so forth because, really why would you?
Anyway, the story follows Mitchell who eventually figures out the kidnapped girl is dead, and never really tells us who the killer is or why he's killing. We do see frequent shots of waves breaking against rocks, which are either symbolic or padding. At the end, we finally see the killer unmasked, but unfortunately have no idea who he is, making the mask unnecessary. To be honest, not a lot of what's happening here is ever explained, which is probably why you can so often find this movie in 99 cent DVD editions.