I get all nostalgic when I think about the early 1970's--that last great era of American movies!
After Bonnie And Clyde (1967), big Hollywood studios did something they'd never done before--they took real risks on a bunch of original, daring movies.
Like Medium Cool, Easy Rider, Two-Lane Blacktop, Badlands, McCabe And Mrs. Miller, The Last Picture Show and Mean Streets.
And Alan J. Pakula's Klute (1971). Jane Fonda plays a New York prostitute in this unsettling thriller. Donald Sutherland is the small-town private eye in the big bad city, looking for a missing person who might have been her john.
The most remarkable thing about this movie is its darkness. There is so little light (deliberately so!) in the way the film is shot that you are literally peering into the screen, trying to make out seen from unseen, light from shadow, good from evil.
The cinematographer, Gordon Willis, was nicknamed "the prince of darkness" because of his underlit style. He was also responsible for the dim, grim look of The Godfather.
That great era of Hollywood experimentation ended abruptly when Steven Spielberg invented something new with Jaws in 1975--the "blockbuster". The rules of the game changed overnight. And alas, we're still playing under those new rules!