I think it was in the 50s or the early 60s at the latest and it was a TV show?? There was a guy who was the only one who could see a dark spot on the foreheads of other people. That spot meant they were going to die. I remember that he saw himself in the mirror and he had a dark spot on his forehead.
Or was this a dream???
Check Out, “Twilight Zone, Season One: The Purple Testament”
Hit the link to see what IMDB has to say about it.
http://www.imdb.com/title/tt0734673/