Well this is un-freakin'-real. I'm sure there's a clever culture-of-life joke out there just waiting to be unleashed, but those sketches are too disorienting to bring anything to mind. Hey, this was also the plot of a Stephen King novel, wasn't it? Only the "twin brother"—mostly some teeth, eyes, a hank of hair—in that instance was lodged in the back of the guy's brain? Can't quite conjure up with the title right now, but that one was nightmare-inducing, for sure.