Youngman Duran: It just doesn't seem natural for a man to spend his life, his entire life, killing bats.
Phillip Payne: Not just bats. Vampire bats. I kill them because they're evil. There's a mutual grace and violence in all forms of nature; and each specie of life gives something in return for its own existence. All but one. The freak. The vampire bat alone is that specie. Have you ever seen one of their caves?
Youngman Duran: No.
Phillip Payne: I killed over 60,000 of them last year in Mexico. You really understand the presence of evil when you go into their caves. The smell of ammonia alone is enough to kill you. The floor of the cave is a foul syrup of digested blood. And the bats: up high, hanging upside down, rustling, fighting, mating, sending constant messages, waiting for the light to fade, hungry for blood, coaxing the big females to wake up and flex their nightwings to lead the colony out across the land, homing in on any living thing; cattle, sheep, dogs, children, anything with warm blood. And they feast, drinking the blood and pissing ammonia. I kill them because they're the quintessence of evil. To me, nothing else exists. The destruction of vampire bats is what i live for.
Youngman Duran: One man's superstition is another man's religion!
Anne Dillon: How could something so evil live in a place so sacred?
Phillip Payne: Doctor, I'd like to show you something. You too, Chee. Now there are four species of flea on this slide: carnivore, dog, X-Cheopis, and bat. I'm going to put a blood spot on the slide. Now what do you see?
Doctor: Well, the bat flea is ingesting the blood.
Phillip Payne: Keep looking. Now what do you see?
Doctor: It's a bacilli. And virulent.
Walker Chee: You mind if I take a look at that?
Phillip Payne: Go ahead.
Doctor: Where did you get that blood specimen?
Phillip Payne: Same place as the fleas: the dead sheep.
Walker Chee: What kind of bacilli is that?
Phillip Payne: Bubonic plague.
Walker Chee: Now how the hell do you know that?
Phillip Payne: It's my business to know.
Walker Chee: What do you think, Doc?
Doctor: Well, it certainly could be plague. What mystifies me is the loss of blood and the stench of ammonia and the bites. I've never seen bites like that.
Phillip Payne: The bite marks come from the incisor teeth of vampire bats. The blood loss and the ammonia are one and the same.
Walker Chee: Meaning what?
Phillip Payne: Vampires consume one and half times their weight in blood. They piss the excess out so they can get airborne again. That excess blood turns into ammonia.
Phillip Payne: Make no mistake. There's a highly intelligent colony of vampire bats roosting in a great cave somewhere in these canyons. Their attacks, inevitably, will be drawn closer to mass human dwellings. And with these attacks come the bubonic plague. That's what you've got to face, Chee.
Walker Chee: What about placing the reservations under quarantine?
Phillip Payne: No, that won't help. You can't protect people from nocturnal sweeps of thirty or forty thousand vampire bats.