Movie clip "roll over" effect on other movie clips

Movie clip “roll over” effect on other movie clips
Sorry if this is simple but I’m very new to flash. The following site does many amazing things…one that I’m trying to recreate is the effect where one movieclip on roll over initiates a move of other movieclips on the main timeline…and then reverses on roll out. I have the reverse effect down…but how can you make one mc effect another mc…or is all just one complex movieclip?

Here’s the site…
http://www.yugop.com/

Thanks