Crime: Vampirism. Suspect: Squirrel!

Scully: “You’re saying that I actually hit him? Two times?”
Mulder: “Square in the chest. No effect.”
Scully: “And then he sort of…flew at me, like a flying squirrel?”

– The X Files, 5X12, Bad Blood

See, and that’s exactly why this is the greatest TV show ever made.