i think it can be done by setting the images to backgrounds in multiple layers and then just moving that layer in front of others.
i remember seeing a basic tutorial a long time ago similar to this for a very simple gallery effect (mouseover a thumb and a larger image appears to the right) but have not been able to find anything similar or as simple.
i would hate to have to cheat and make a separate page with identical content except for the ■■■■ picture.
would appreciate any help on this noob question.
attached is a very rough diagram of what I’m trying to do.