upper crust

Fig. the higher levels of society; the upper class. (From the top, as opposed to the bottom, crust of a pie.) Jane speaks like that because she pretends to be from the upper crust, but her father was a miner. James is from the upper crust, but he is penniless.

The highest social class, as in She wanted badly to be one of the upper crust but it wasn't going to happen. This term alludes to the choicest part of a pie or loaf of bread. [First half of 1800s]

The top level of society. Although you might think that “crust” refers to bread and that the upper part was reserved for the aristocracy, word detectives would say you're wrong: no authoritative written connection between bread and the well-bred can be found. “Crust” refers to the earth's crust, or top layer. The upper crust of a society is its top layer.