After a long day of work as a New Jersey prison guard, Linus Hather wakes up one night to find that his high-tech security system has caught an unexpected intruder. Upon seeing it, he calls his old college buddy who is a biology professor and he comes to Linus's house and tells him that he's captured a new man-related species (a hominid) that will change the world (in the same way that capturing a Bigfoot would)! His friend and the other scientists who come to take the creature away pronounce it as “not dangerous”. But Linus has evidence (or Had!) that the creature is a killer and was actually on his way to kill Linus that night. He has no luck convincing his friend, or the scientists, that the creature is a threat.Much to the scientists' chagrin, it has escaped, and not only does the creature turn out to be dangerous, but basically it's a serial killer. And if that's not enough bad news, the evidence is stacking up that there appears to be more than one “creature” out there.Linus is set upon a path to find this killer before it kills again, but it turns out that he's pursuing the stealthiest mankiller that has ever lived and he'll need the help of many reluctant new friends from the four corners of the earth if he's going to have any success at capturing the Devil's Assassin.