It looks like 'Dumb & Dumber' could totally work as a suspense/dramatic film! Check out how the film's premise & mood can totally change with just some creative editing:

Dumb and Dumber as an Epic Drama from Josh Rocklage on Vimeo.

Reminds us of the 'Mrs. Doubtfire' redone as a horror movie, which is also excellent if you haven't seen yet: