Select-String for all .json files in many subdirs, output needs full path

I have a call recording program that dumps every customer service call our company answers into a folder structure by Year, Month, day, and hour and finally call ID. In this folder is the encrypted call file and a file called meta-data.json which is a text file with metadata pertaining to the call like agent name, caller ID info and phone number etc.

What I need to do is to be able to search these thousands of meta-data.json files in thousands of subdirs and find strings of text and a full path to the file(s) containing the text.

This is about as far as my powershell skills can take me (and I had to google it...) Lets say I am looking for calls taken by agent Justin.

Select-String *.json -Pattern Justin