the-apartment
The Apartment (1960)
Best Line: “You would think I should have learned by now. When you’re in love with a married man you shouldn’t wear mascara.”
This Billy Wilder-directed film about marital infidelity (and so much more) is pure hilarity no matter what generation you were born in. Starring Jack Lemmon and Shirley MacLaine, it does a better job of satirizing corporate culture and sexual hypocrisy than any comedy that’s come before or since.