I need a help for flash scripting.?

I had made a two different movie clip for web design company client one is a scroller another movie clip contains some images in scroller movieclip I had put some buttons. Now when we click first button a particular image should appear in 2nd movieclip, when I click 2nd button another image should appear. but I am not able to give a perfect script to button so that it link to another movie clip. Can pls. someone can help me.