How can i call a .swf from within an attachMovie clip

complete beginner question
Any tips would be wonderful…
Am creating a flash site, with menu, and sub menu that appears on roll-over… the sub menu is an mc (with buttons inside) which does not exist on the main timeline, is called there by attachMovie…
how can i make those buttons in the attached movie call up an .swf (containing content for the site)??
honestly grateful for the smallest response,