In our final Halloween special, we sink our teeth into the viral origins of zombies—from fast-moving cinematic ghouls to real-world pathogens like rabies and cordyceps. We explore how zombie lore mirrors epidemiological principles and how public health campaigns, like the CDC’s zombie preparedness guide, use fiction to drive real-world readiness. It’s a chilling reminder that emergency planning is all about asking “what if”—even when the answer is undead.