During the Cold War, the U.S. military created a superhuman compound called Formula X, but the project failed and its testing bunker was sealed and abandoned. In 1991 — seven years before the Curien Mansion Incident — rookie AMS Special Agent G receives his first assignment: travel to a small Louisiana town to investigate a string of disappearances and bring down a deranged crime boss, Papa Caesar. With mutants roaming the area, G is forced to partner with police detective Isaac Washington, who is out to avenge his father, murdered in a killing Caesar orchestrated.