It's a now commonplace observation that Bannion spells doom for every woman with whom he comes in contact, but is that true? The junkyard secretary, Selma, survives contact with him, even when she is enlisted into (dangerously) identifying a third character.
On this rewatch, I also found the so-called 'upbeat' ending more than a little hollow... and this is to Lang's credit. Bannion is welcomed back on the force with a smile and clean desk, yet by my moral compass he absolutely murdered Gordon by spreading it around that he was a rat, even if he did not pull the trigger himself. I'm also of the opinion that, perhaps subconsciously, he intended Debby to kill Bertha so that the secret would come out. Oh, and Debby's seeming desire to die at the end (she must know that Stone has a gun) is haunting.
There isn’t an ounce of fat on this film, and, for Lang and screenwriter Sydney Boehm, conventional human sentiment is often considered fat.[…]
Dying on a fur coat, her instrument of her living—her sexiness—cruelly tarnished by abuse, Debbie asks Bannion about his wife, wishing to die with an image of a woman who made it into the sort of “mainstream” society that eluded her. Bannion yearns for his wife himself, of course, and this masterpiece’s one true moment of human communion is achieved when two characters, from opposing castes, realize that they’re both chasing the same damn dream of belonging, which they both understand to have blown irrevocably away.
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Only the women die, but they’re also always revealed to be pulling the highest strings. Both the protagonist and the antagonist are haunted, and driven, by dead women.
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[In the commentary on the Twilight Time DVD], Scorsese, unsurprisingly given his own obsessions, homes in on how the hero’s quest warps him, and perceptively acknowledges the film’s formalism to be both “flat” and expressionist at once, which is probably the key to its weird power.
— Chuck Bowen (Slant Magazine)
While [Bannion] cannot bring himself to break his own moral code, the women around him, by mere association, suffer for his internal conflict. Bannion presents a rare homme fatale who, however inadvertently, spells doom for every woman with whom he comes in contact. And while women have the most interesting roles in this exquisitely acted film, most have been fated by their contact with the tragic hero, a living symbol of the need to persist in the face of America’s systemic corruption, crime, and injustice.[…]
Misogynistic violence often diffuses or incites an unruly femme fatale in film noirs. The classic femme fatale resists domesticated roles and seeks independence, often through violence or the manipulation of men. Everyone around them seems to die, whether by direct or indirect action on her part. But the genre itself attempts to restore domestic order to the femme fatale by eliminating her. […] Look at the poster for The Big Heat, which shows Bannion twisting Debby’s arm behind her back. This never occurs in the film; it is Stone who bends Debby’s arm in the film. Likewise, promotion stills show Bannion gripping Debby’s hair in an aggressive way, another scene that never occurs in the film. […] Columbia’s promotional department taps into some unconscious element of the 1950s viewing audience that wanted to bring harm to women, to correct them through acts of violence.
— Brian Eggert (Deep Focus Review)