Influenced by silent films produced several decades earlier, particularly German Expressionist films, a lot of the film looks like it was cut out of black construction paper and pasted to a lamp. This starkness of imagery is mirrored by a story comprised of finely distilled components--of character, plot, and themes. Robert Mitchum single-handedly embodies religious and sexual hypocrisy as well as delusional psychopathy while Shelley Winters, over the course of, I think, less than a month runs a path from lost and grieving widow, seduced and deceived woman, religious zealot, and finally a martyr for a sort of basic, naturalistic decency in the face of delusional and destructive logic.
This idea of the basic goodness of nature seems to be the force of good standing in opposition to Mitchum's bludgeon of a more abstract and cold sermonising. His famous "LOVE/HATE" knuckle tattoos bespeak a philosophy that brooks no middle ground.
It makes sense then that, as a contrast, Lillian Gish, the film's apparent epitome of what director Charles Laughton considered good, would sing along with Mitchum the eerie hymn as he stands outside the house, waiting for a chance to steal and murder. It's also the only perspective that makes sense of the child John's sudden sympathy for Mitchum's character at the end.
Like much of the film, the children work both as a visceral reality and conspicuously artificial stylisation. There's something almost Victorian about the way the filmmakers insist on their purity, and yet one of my favourite scenes in the film is when Mitchum shows the little girl his knife.
There's something very authentic about the way she at first seems weirdly offended by it, but then, slowly, she approaches wanting to take it. She clearly never sees him as any kind of villain and although the initial sight of the knife is a little unnerving, if "daddy" says the knife's "cute," then she's interested in it. That we've already established the knife as a phallus in the scene at the burlesque show where Mitchum compulsively stabs through his pocket with it makes the later scene take on an even more disturbing subtext.
All the stark black shapes of the film's visuals help emphasise the strangely interior quality of the story. It feels cut off from society, almost like the psychological effect of Sylvia Plath's bell jar--the struggles between the characters have the festering reality of passion and logical houses of cards manifested after a long period in solitary confinement.