Passion Beach (1973)

Jason just arrived from Johanesburg and visits a deserted beach house, which belongs to his best friend Mihalis. There he finds Mihalis's wife, Mary, with her sister Magda and a weird fisherman named Kosmas, that stays with them, but seems to somehow, bullying them. He decides to stay with them waiting for his friend to arrive and find him there, but also because he falls in love with Magda. While Jason is having good time with his mistress, things get complicated when he discovers that the fisherman is not what he says he is and at the same time two suspiciously looking characters appear and are stalking the young couple's, every move..