Loading html from external file into div

Loading html from external file into div

I'm fairly new to jquery so apologies if this is a very simple question with a very simple answer, but I just can't figure out the solution.
 
I have an overlay div, and when I close the overlay I want to remove the html inside it and then re-load it from the specified file. I have already worked out how to empty the div, but what I now want to do is re-populate it with the content from a separate file on my web server.
 
Here is my sample code:
 
  1. onClose: function() {
  2. $("#video-popups").empty();
  3. // what do I insert here to repopulate the div with external content?
  4. }