"* What are the identifying characteristics of film noirs?

For instance, some critics insist that a film noir, to be authentic, must have a bleak conclusion (e.g., Criss Cross or D.O.A.), but many acknowledged classics of the genre have clearly happy endings (e.g., Stranger on the Third Floor, The Big Sleep, Dark Passage, and The Dark Corner), while the tone of many other noir denouements is ambivalent, in a variety of ways. The ambition of this section, then, can be no more than modest: it is an attempt to survey those characteristics most often cited by critics as representative of classic film noirs. As diverse as that set of movies is, the diversity of films from outside the classic period that have been discussed as noir is so great that any similar survey would be impractical; however, those classic noir identifying marks often referenced in neo-noirs—however frequently or seldom they actually appeared in the original films—are noted as are certain signal trends of the latter-day mode."


"The tone of film noir is generally regarded as downbeat; some critics experience it as darker still—"overwhelmingly black," according to Robert Ottoson.[32] Influential critic (and filmmaker) Paul Schrader wrote in a seminal 1972 essay that "film noir is defined by tone," a tone he seems to perceive as "hopeless."[33] In describing the adaptation of Double Indemnity, leading noir analyst Foster Hirsch describes the "requisite hopeless tone" achieved by the filmmakers, which appears to characterize his view of noir as a whole.[34] On the other hand, definitive film noirs such as The Big Sleep, The Lady from Shanghai, and Double Indemnity itself are famed for their hardboiled repartee, often imbued with sexual innuendo and self-reflexive humor—notes of another tone."
(http://en.wikipedia.org/wiki/Film_noir)

就算是那個年代的經典, 也不是都符合這個標準.