I'm a bit confused: I'm used to reading "Did you see that" rather than "Have you seen that", but I'm no English major. That cliffhanger though... (It's a secret alien base, that's what.)
@Ncararc
I was really conflicted on that bit. I know that past simple would be preferable here, but there is a parallelism for comic effect, and I struggled to convey it properly (and I still missed it, I suppose).
I'll change it when (if at all) I figure this out.