[not the javascript kind]pop up flash window; dimming the movie

I am trying to create a fake pop up window in flash. what i mean is on some flash sites when you click an element the flash movie appears to dim and a box(pop up window) will come up with a picture or something. then you hit close and the box goes away and the movie goes back to the original state. Does this freeze the main movie? I am not sure what to search for on this topic. Any ideas?

thanks
earl