How do you use MovieClipLoader to load in a sequence

1

I am trying to load a movie clips on after another. One is a longer intro animation so i do not want to add keyframes to the main time line. what i want to tell it to do is, "if load completed on intro.swf then unload clip intro and load clip “backdrop.swf.”. if they load together one will cover up the others animation (i do know about loading them into different levels in flash but that will not work). thanks chris