A 1927 novel by Sinclair Lewis that was made into a 1960 movie, written and directed by Richard Brooks.
Sister Sharon Falconer (Jean Simmons) is doing moderately well in the tent revival
racketbusiness when, one day, a traveling salesman by the name of Elmer Gantry (Burt Lancaster) walks into the tent. Gantry is taken with Sister Sharon; she is mesmerised. Soon, Gantry is sampling Sister Sharon's charms while applying his proven sales techniques to preaching, and the money comes pouring in.
The trouble is, Elmer Gantry is not of the most saintly character: He is a narcissitic personality who drinks like a fish and chases down anything female. Sister Sharon looks the other way while they build their empire; Gantry slowly corrupts her minstry and her as well. While newspaperman Jim Lefferts (Arthur Kennedy) ferrets out Gantry's secrets, Lulu Baines (Shirley Jones) tries to blackmail Sister Sharon with evidence of Gantry's behavior. At the moment Sister Sharon realizes what she has become, she is killed when her tent catches fire.
Brooks changed Sinclair Lewis' novel around quite a bit: From Lewis' dark description of an irredeemable, cynical womanizer who shakes off Sister Sharon's death and starts a new
scamministry, we get a Gantry who realizes that he believes what he preaches, and turns over a new leaf, walking away from his own cult of Mammon forever. You will recognize large sections of the plot as a retelling of the events that brought down Aimee Semple McPherson.
Regardless of that (and despite the fact that The Apartment beat it out for Best Picture), Elmer Gantry is one of the greatest films ever made. Burt Lancaster's Oscar-winning performance has to be seen to be believed. Shirley Jones also won an Oscar for Best Supporting Actress.
See this movie!