know who's who
To know details about or have connections with everyone or many people in a group. Usually used in relation to groups of rich, powerful, or famous people. I feel like a total fraud in this relationship. I mean, she knows who's who in the ultra-rich upper class of Maine, while I'm just a poor bartender who's going to community college. If you want to get ahead in this industry, you need to know who's who.
Farlex Dictionary of Idioms. © 2024 Farlex, Inc, all rights reserved.