As we all knew he would be, Eugene Victor Tooms is back and loose ready to find his final victim so he can go into another hibernation period for 30 years.

At the start of the episode we see Eugene being held in a court of law with Mulder ready to give his testimonial so he has a chance that Tooms may stay back inside. It is not to be though as Mulder gives an outrageous presentation telling the court that he is a genetic mutant over 100 years old who eats human livers! This prompts the court to quickly let him go. Mulder argues telling the court that "If you release Eugene Tooms he will kill again" but this does not change the decision and we see Tooms' scary smirk at the agents as he walks away ready to kill again.

Mulder doesn't give up though and keeps a close eye on Tooms while Scully is warned by Walter Skinner to give up on this case and keep a good record in the bureau while 'Cancer Man' watches in on the proceedings. Later Scully decides to contact Det. Frank Briggs who helped the agents catch Tooms previously. He directs Scully to search a factory where he believes that one of Tooms' victims is buried. They find the body along with what look like Tooms' teethmarks in the rib cage.

Meanwhile, Mulder dozes off while watching Tooms but manages to wake up in time to stop an attempted murder. Tooms though crawls out of the bars of a window. Scully later joins Mulder but he tells her to go home as he fears that her career may be ended because of him. It is Mulder who goes home in the end to Scully's urging but Tooms hides in the trunk of his car while on the way home.

Tooms enters Mulder's appartement through a vent and uses his own finger to cut his face and one of Mulder's shoes to beat him in the jaw. He also disgustingly dislocates his shoulder. He then accuses Mulder of beating him which prompts Skinner to tell Mulder to take a break and stay away from Tooms.

But Tooms manages to find his fifth and final victim in the shape of his psychiatrist who managed to fight for his release. The agents discover the body and realize Tooms must now be beginning his 30 year hibernation period. They think that he must be going back to his old appartement but when they find out it has been turned into a mall they rush there. Mulder realizes he must be under an escalator where Tooms challenges him only for him to come to a gruesome demise when Mulder turns the escalator on.

Back at the FBI headquarters, Skinner reads the report of the case and when he asks Cancer Man whether he believes it he replies "Of course I do". Meanwhile Mulder remarks to Scully while looking at a caterpillar cocoon that "Change is coming" for the X-Files. He doesn't know how right he is.