Shelton, Oregon was once a nice city right on the coast. That all changed after The Vorcino Virus Outbreak of 2007. Now, twenty years later, the city is surrounded by high walls and constant screenings of its citizens. A forced eradication of all infected has been enforced to protect the citizens from the dangerous infected, known as vampires.
A Beast Within follows Bill Draig, a network administrator with the Vasquez Corporation, who has just been promoted and is out celebrating with his friends. After a night of heavy drinking and bad decisions, Bill discovers that he has become the first person infected since the original outbreak. While running for his life he meets three people who will forever change his life. Erika Lorenz, a highly intelligent college student who is stripping her way through college. Vasille Fonentouix, the co-leader of a hidden group of "vampires" who wants to help Bill. Constantine Collins, a once brilliant scientist who has become a psychopath who is determined to free his people from the tyranny of the local populace. A mysterious and violent ancestry, a prophecy, and Constantine's never ending war on humanity all converge in a final battle for the fate of the world.
A Beast Within mixes medical science fiction with fantasy elements to bring about a unique view of vampirism while detailing the social issues faced by those infected with the disease.