Different pages shown depending on login (non-users)

Hi,
I’m looking for a plug-in that will, after logged in, show different pages on the site depending of the user/password. Those who will log in are not users on the page.

There are two different access groups. For one of them, a lot of pages shall be hidden. The best would be if it was possible to control which pages are shown through the menu, ie, different menus appear, depending on who is logged in.