Google Map show Circular Shadow/Coverage Zone with specific Radius --

Google Map show Circular Shadow/Coverage Zone with specific Radius --

Hello and greetings.

I have a unique requirement. It involves google maps etc. I have the Lat, Long of a particular place, stored in db of course. Now I want to show a circular shadow zone like a coverage zone [of a light/faint colour like aliceblue] on the map that loads on my web page, with that place as the centre of the circle. The radius of this circle will be 7 km. Is this at all possible? If so, can you lead me step by step to developing this functionality? What are the plugins I need to do this? 

I have no shame in admitting that at this point, I have not the requisite theoretical knowledge to implement this. I am confused. But I cannot stress enough as to how important and mandatory it is that I finally implement this in my application. That is why I turned to the forums. Please help me. I am counting on the collective knowledge of forum members.

Many Thanks in advance. God Bless.