Ooooh I love this sort of thing. I love coming up with random weird ideas.
Here's one I might never end up making myself so I'll put it here: A young alien lands on a post apocalyptic earth and visit's the only remaining human buildings (a major attraction), only to find scraps of newspapers and old diary entries that talk of strange creatures who come in glowing craft and attempt to destroy all human life...
Weird Idea but maybe there's something there.