Stupid question about load movie


I have 3 loadMovie in 3 different containers at the begining of the main movie.
How does flash react to this. Does it load each movie one after the other? Or does it start right away to upload all 3 movies at the same time?

I was wondering the above for preloader reason. As the main movie opens with only movie1 showing up (the other 2 being uploaded to be ready on call are set on invisible), I am not sure if adding a preloader only to movie1 and let the other 2 upload in the background or preload all 3 movies at the same time.:ponder: