This 35mm screening is part of the BFI's 'Ride Lonesome: The Psychological Western' season. You can find full details here. This film is also being shown on May 1st.
Chicago Reader review:
A big, big western (1946) from producer David O. Selznick, with Jennifer Jones, Joseph Cotten, Lionel Barrymore, Gregory Peck, Lillian Gish, Herbert Marshall, Walter Huston, Harry Carey, and Butterfly McQueen. Selznick enlisted King Vidor—one of the few directors with the logistical know-how to handle such a sprawling film—and tried to duplicate the success of his Gone With the Wind. What Selznick got instead was a screaming Freudian fantasy, full of the dark sexuality characteristic of Vidor's late career (Beyond the Forest, Ruby Gentry). Contemporary wits called it Lust in the Dust, and there's no doubt that it goes too far in almost every direction—but that touch of obsession is exactly what saves it.
Here (and above) is the trailer.