apocalyptic ... they signal the end of the world as we have known it". While zombie apocalypse scenarios are secular, they follow a religious pattern based on Christian ideas of an end-times war and messiah. Simon Pegg, who starred in and co-wrote the 2004 zombie comedy film Shaun of the Dead, wrote that zombies were the "most potent metaphorical monster". According to Pegg, whereas vampires represent sex, zombies represent death: "Slow and steady in their approach, weak, clumsy, often absurd, the zombie relentlessly closes in, unstoppable, intractable." He expressed his dislike for the trend for fast zombies, and argued that they should be slow and inept; just as a healthy diet and exercise can delay death, zombies are easy to avoid, but not forever. He also argued that this was essential for making them "oddly sympathetic... to create tragic anti-heroes... to be pitied, empathised with, even rooted for. The moment they appear angry or petulant, the second they emit furious velociraptor screeches (as opposed to the correct mournful moans of longing), they cease to possess any ambiguity. They are simply mean." Story elements Initial contacts with zombies are extremely dangerous and traumatic, causing shock, panic, disbelief and possibly denial, hampering survivors' ability to deal with hostile encounters. The response of authorities to the threat is slower than its rate of growth, giving the zombie plague time to expand beyond containment. This results in the collapse of the given society. Zombies take full control, while small groups of the living must fight for their survival. The stories usually follow a single group of survivors, caught up in the sudden rush of the crisis. The narrative generally progresses from the onset of the zombie plague, then initial attempts to seek the aid of authorities, the failure of those authorities, through to the sudden catastrophic collapse of all large-scale organization and the characters' subsequent attempts to survive on their own. Such stories are often squarely focused on the way their characters react to such an extreme catastrophe, and how their personalities are changed by the stress, often acting on more primal motivations (fear, self-preservation) than they would display in normal life. Literature In the 1990s, zombie fiction emerged as a distinct literary subgenre, with the publication of Book of the Dead (1990) and its follow-up Still Dead: Book of the Dead 2 (1992), both edited by horror authors John Skipp and Craig Spector.