The femme fatale is second only to the hardboiled private eye as a noir archetype. The origins of the private eye archetype are in the pulp magazines from which film noir drew a lot of stories, but the femme fatale goes all the way back to Helen of Troy.

A femme fatale is a dangerous woman, a woman who uses her charm and her beauty to get what she wants- often by manipulating and duping a private eye. This is the theme of the very first noir of all, “The Maltese Falcon,” but Bogart as Sam Spade turns the tables on femme fatale Brigid O'Shaughnesy in the end. This is a typical development for a lot of noir movies, although sometimes it ends very badly for the detective as well, as in “Out Of The Past.”

Because of this pattern- in which the femme fatale is eventually punished for attempting to use her sexuality to gain power over the male lead- some critics have seen the whole femme fatale type as being basically misogynist. I'm not sure if that's always true- if you go looking for misogyny everywhere, you're bound to find it everywhere- but it's definitely true of some examples. In Micky Spillane's “I, The Jury,” his detective callously murders his femme fatale girlfriend (a rather amusing parody of Spillane fan Ayn Rand) in a context that seems brutally and consciously misogynist.

Other critics take the exact opposite view, seeing the femme fatale as a symbol of feminine independence. With certain exceptions, I don't agree with either interpretation. I would say that some people are just manipulative and dangerous, some of those people are women, and that makes for a good story.