John Cazale (August 12, 1935 - March 12, 1978) had a very brief career in films. He was in just six movies from 1972 to 1978. Each of the movies was nominated for an Academy Award for Best Picture (he's the only actor with multiple roles to have each of his movies nominated). All six are in the IMDB Top 250(he's the only actor with multiple roles to have this honor).
I just watched The Deer Hunter which was his final role. It's also the movie where he met his fiancee' at the time of his death, Meryl Streep.
Here's a list of his six movies: