Written on the Wind (1956)

This woman in his arms was now the wife of the man he called his best friend!

Mitch Wayne is a geologist working for the Hadleys, an oil-rich Texas family. While the patriarch, Jasper, works hard to establish the family business, his irresponsible son, Kyle, is an alcoholic playboy, and his daughter, Marylee, is the town tramp. Mitch harbors a secret love for Kyle's unsatisfied wife, Lucy -- a fact that leaves him exposed when the jealous Marylee accuses him of murder.