Displaying part of sprite that overlaps with other gameObject

I am making a game where a player is walking through a dark maze. The majority of the screen will be pitch black, but a circle centered on the player will "illuminate" enemies. How would I make the enemy sprites pitch black, except for the portions that overlap with the circle? The answer seems to be with using shaders, but the issue I found is that the answers online are usually to have the circle hide the enemy, rather than display them. Keep in mind I am also not very experienced with shaders.

Thank you.