However we might imagine we’ll act in an emergency, we really don’t know until it happens. One person, having mentally rehearsed a disaster response, may react as he or she planned. One who has dreamed of saving the day might instead panic, whereas a cynic who scoffs at heroism, assuming that “I’ll never risk my neck for any stranger,” in the heat of the moment sometimes does exactly that. When no plan is possible or when a crisis seems too unlikely to be anticipated, posttraumatic reactions can be especially severe. In the world of The Walking Dead, where nobody has ever seen a Living Dead film, no one expects the zombie apocalypse.