Nightmare (1965)

Fashion-designer May Berg is driving alone one evening, when she almost run over a man lying in the street. She gets out of the car to see. Suddenly the man attacks her, trying to strangle her. The assassination attempt fails, but it is followed soon by new, mysterious attempts to kill her. She is driven more and more into a constant fear of her life. Her husband trivialize the whole thing and even the police is skeptical of her claims that she is stalked by someone trying to kill her.