Loading Movies from buttons

I have a question,

I have 6 buttons. Each one of them loads a movie using the [font=Courier New]LoadMovie[/font] command. Say when I press button 1 it loads movie 1, when I press button 4 I want it to unload movie 1 and load movie 4, but my question is, how do I tell the button to unload “any” movie loaded from previous buttons and load the new movie for that button? is that confusing?

WHat’s the action script command for that?

Thx!