CSS - Non-interactive Div

Ok, here's a weird one (at least to me).

We have a div that contains various elements. We want the elements to show but to be completely unusable until a flag is toggled. In essense everything on the div should be completely non-interactive, in fact, if there's something like a link or button under the div we want a click on the div to interact with whatever is below the div. Nutty, huh? But can it be done?

Any help appreciated.