In the 21st century, scientists discovered that a mere five mutations can transform a simple virus into a plague the likes of which we have not come across since the Dark Ages. A plague that could alter the very facet of our lives. In 2018, a disease borne by livestock threatens to transform into the penultimate version of the worst epidemic of our time. Symptoms vary from patient to patient. Commonalities include mind-numbing pain, seizures, organ failure, and sudden and inexplicable death. News of the illness is buried beneath headlines of various refugee crises, tectonic shifts, and worsening international relations. Is this a simple oversight or, as those in the fringes of society claim, purposeful ignorance? Amidst the turmoil, Aydin and Salar are young men on a mission. Performing gruesome backyard experiments, they are in a race against time to save Aydin's younger sister from the fates of the other infected. On the other side of the globe, Garrett Asher follows in his estranged father's footsteps and joins the military branch of the World Health Organization, headed straight for Aydin and stumbling over dark secrets along the way. Protect your loved ones. Shield your blood. Beware of Mutation 4.