In Left 4 Dead, a strain of the Rabies virus was accidentally released in the United States. The virus turned everyone who made contact with the virus into zombie-like creatures. These zombies were referred to as the "Infected." Upon these infected humans, there were common infected, which were regular zombies, and Special infected, which were different infected with different powers. The special infected consisted of Hunters, zombies with hooded sweatshirts that could pounce on survivors from great distances, Smokers, zombies who could ensnare survivors with their long tongues from long distances, Boomers, fat zombies that threw up on survivors to attract the hordes of common infected, the Witch, a female zombie with great power that could kill almost any human, and the Tank, a huge, hulk-like zombie that is almost impossible to kill. After the infection broke out, four immune survivors fought their way through the hordes of infected to make it to the various safe points throughout the United States. These four survivors were Francis, a tough, smug biker, Bill, an old army veteran from the Vietnam War, Zoey, a young woman in her twenties, and Louis, an African-American accountant. These four made it to various safe points and stuck together to fight off the infected. In the end, the four survivors escaped from Allegheny and are on their way to quarantine zone Alpha…