SAM MENDES has the unenviable distinction of having directed one of the three most undeserving Best Picture winners in the last 30 years. In 1999, his directorial debut, American Beauty, won the Oscar and then, immediately, began sliding to oblivion. A paint-by-numbers critique of American middle-class mores, American Beauty was so heavy-handed and obvious as to be insulting even to the elite sophisticates it attempted to flatter. Of course experimentation with marijuana brings happiness. Of course the homophobic, wife-beating Marine father next door is really a closet case. Of course the only well-adjusted adults in the neighborhood are the...