You remember that old movie "The FlY'? I went to it expected something erotic and it wound up being a Vincent Price scary movie.
There was this guy who was trying to transport himself from one place to another but he hadn't noticed a small fly had gotten in there with him.
So the fly winds up with a human head and the human winds up as a two-footed giant fly.
And boy was he mad. I mean, not only had he failed in his project but he knew he only had 15 days to eat shat and die!