More religious themes in Greene's Brighton Rock

Following up on yesterday's post on Graham Greene's Brighton Rock (1938), which as indicated from the first sentence becomes a crime story, of sorts, with two rival gangs jostling for control of the betting operations at the nearby race track - the upstart gang led by a 17-year-old, Pinkie, who is cold-blooded and has no remorse about killing one of the gang members who in some manner betrayed the group and slashing the face of a guy who didn't pay off his gambling debts. The established gang is led by a true mafioso type, can't remember his name but it might as well be Corleone, who is cool and distant and lives a life of luxury and is somewhat taken by the Pinkie's fearlessness -but also ready to squash him if need be. Pinkie's problem is that a young (16) waitress at a seaside place witnessed some aspects of the murder and he has to keep her quiet; he flirts with her for a while, at which point we learn he is essentially asexual - his flirting is just a business proposition. In fact, he's repulsed by her and by the whole concept of sex. Both he and the girl, Rose, are "Romans," but Pinkie has no faith, no belief in mercy or salvation - though he recognizes that many plead for mercy when in the face of death. Another witness to part of the murder, a 40-something woman, Ida Arnold, becomes increasingly - and foolishly - curious about what happened (she'd met the victim but had not real relationship to him) and she begins following a # of leads and clues to prove that the victim, Hale, was killed and didn't die of natural causes, as the so-called inquest ruled. She is like a pilgrim, seeking the truth. Many potential conflicts loom: between Pinkie and his somewhat recalcitrant gang, Pinkie and "Corleone," Pinkie and Ida, Ida and the (paid off?) police - and it seems all this will culminate at the race track. Just wondering: Was the movie Atlantic City, which I saw so many years ago I forget all the plot details, based on this novel, transposed to the U.S. ca 1970?