Zeb Smith (Wild Bill Elliott) is a no good tinhorn gambler who doesn't think much of an old preacher (H.B Warner) who tries to save his soul in a shady saloon, but he thinks twice after he gets caught with some cards up his sleeve and the preacher steps in front of a bullet meant for him. As the old preacher is dying, Elliott promises to fulfill the old padre's dream - to build the church he was collecting funds for. The catch is he has to do it by the rules as laid down in the Good Book, which Zeb has never read. As Zeb sets out on this quest, we see he is slowly converted in both belief and character by reading the Bible. His efforts to follow the "rule book" are generally met with scorn and hostility by the people he encounters, particularly the wild lady outlaw Doll Brown (Marie Windsor). She hooks up with Zeb hoping to escape Marshal Bucky McLean (Forrest Tucker) and the vengeful Stoner brothers, a motley trio that includes western regulars Jim Davis and Paul Fix. Zeb originally hopes to convince her to change her ways and to turn herself in - which would gain him enough reward money to fulfill the late preacher's dream of building the church. Zeb however finds himself in a difficult position in trying to gain her trust, while also risking becoming a wanted man himself as he aids Doll in her flight from justice.

HELLFIRE stands out by virtue of its unusual religious angle, which is carefully integrated into the standard Republic Pictures B-western framework in a way that strikes the viewer as much more dramatically sound and emotionally honest than if such a plot had been treated in an A-western. Just imagine how sanctimonious THE GUNFIGHTER or SHANE would have been if the title characters, played by Gregory Peck and Alan Ladd, respectively, had suddenly found religion. The strength of HELLFIRE is its acknowledgment of the difficulty of grappling with a new-found faith in the violent hard-boiled landscape of the Republic Pictures western. The hero is only slowly finding his way and is still bound by such old habits as using his fists and firing his gun when trouble rears its head. Elliot is good as always, but this is clearly Marie Windsor's show all the way as she propels the action and provides the emotional core (and heart-wrenching finale). The film is shot in that beautifully harsh palette of Trucolor that turns everything blue-green or orange-brown, giving the proceedings an otherworldly alternate-pulp western-dimension look.