Left 4 Dead 2 is better than its predecessor in nearly every possible way. It's more demanding, more varied, and more entertaining. Once again, this is the story of four human survivors and their desperate, bloody bid to outrun a zombie apocalypse. We're finally told what happened to unleash hell on Earth as the group attempts to travel from Savannah, Georgia to New Orleans, Louisiana. Five individual campaigns are linked to form a loose story that adds context and detail to the world, but still serves primarily as a framework for zombie-killin'.