It strikes me as odd after all the years of railing against the femme fatale as a defining premise in noir you would be so tenacious in trying to locate it in films where such female characters are permitted more latitude for treachery primarily by the conventions of the sub-genre, but it appears to be needed in order to establish what is a tenuous and incomplete thesis concerning the development of film noir. The “peril-inducing character” need not be a femme fatale, as a look at Siodmak’s INQUEST or Duvivier’s MOON OVER MOROCCO (both 1931) demonstrate. But female treachery and sexual manipulation quickly become a template the next year in NUIT DU CARREFOUR and AU NOM DE LA LOI, and while this manipulation is not as overt (overstated?) as it would later become, it is clearly present. As for Vincendeau, her description of Winfried is ridiculous—she is clearly a sexual predator, not merely a tramp. And LA TETE D’UN HOMME does not rise or fall in terms of its “noirness” due to the female shrew but because of the spectacularly overwrought character arc of the villain (Valery Inkijinoff, egged on by Duvivier to act out a psychotic break that makes Peter Lorre in M seem like a simpering weasel by comparison).
The ultimate problem with spy noir is that it leads to its own sub-genre that is less “noir” than what emerges in the 40s and that peels off into a dynamic that is long on intrigue but short on alienation or corruption—specifically personal corruption or what Mike Keaney calls “character disintegration.” Spy noir does a fine job of sharpening the tools of treachery but it lacks an actual psychological component to make it credible beyond its manipulation of the narrative (plot elements). It can utilize oppressive physical space, but it cannot really convey a pervasively oppressive atmosphere, which develops in the woman-in-peril and haunted character sub-genres. As noted before, it’s a fine addition to our overall knowledge of the sub-genres that contribute to the spread of noir in the 30s but it is not the primary catalyst for it and it diverges from the seminal direction—towards alienation—that noir coalesces around in the 40s.