Some French words and expressions commonly used in English:
Fait accompli done deed
Fait accompli seems more fatalistic than done deed, which is so factual.
Faux pas false step, trip
Something that should not be done, a foolish mistake.
Femme fatale deadly woman
An alluring, mysterious woman who seduces men.
Fiancé, fiancée engaged person, betrothed
fiancé refers to a man and fiancée to a woman.
Film noir black movie
Black is a literal reference to the stark black-and-white cinematography style, though films noirs tend to be figuratively dark as well
Also: Déjà Vu