A mysterious plague is ravaging Cybertron, and it couldn't have come at a worse time. With the Great War already creating massive casualties, the last thing they needed was a plague. After escaping the destruction of Iacon by the skin of his teeth, Ratchet is transferred to a medical center where his expertise is desperately needed. While stationed there, he begins to study the plague in the hopes of finding answers. Who was responsible for this? Why did they do it? As the days pass, bodies show up with no explanation as to how they got there. Ratchet is overwhelmed with evidence, but has no idea how to use it. Until the would-be perpetrator makes a shocking appearance.