The Beginning

Mulder and Scully appear before the supervisory board to justify the need for their return to work on Classified Materials. The Council demands scientific evidence of the existence of extraterrestrial life. Mulder tries to explain that Scully, who has been infected with an alien virus, can become such proof. However, Scully is vague about this infection, and the council gives them one last opportunity to present evidence.

Skinner secretly leads Mulder to a strange case in Arizona that could help him gather the necessary data. At the scene of the crime, Mulder assumes that the victim was infected with an alien virus, resulting in the birth of an alien creature, while tearing the chest and abdominal cavity of the carrier.

The syndicate is unhappy that this "situation" attracts too much attention. The smoker guarantees that he will take care of this problem. He brings Gibson Price, a young chess genius, to the crime scene, in the hope that he will be able to predict where the creature will go. Mulder and Scully go to a nearby power plant where another murder has been committed. There they are met by Agents Spender and Foley, who deny Mulder access to the scene of a new crime. When Mulder and Scully return to their car, they find Price hiding in the backseat. Mulder also wants to use Price to find an alien creature, but Scully dissuades him from doing so, explaining that Price is the very scientific evidence that Mulder is looking for. Price can confirm all of Mulder's statements. When Scully informs Mulder that Price needs medical attention and that she is going to take him to the hospital, Agent Foley approaches. Scully leaves with Gibson for the hospital, and Mulder and Foley go to the power plant to find the creature. On the spot, they find out that the alien is still there. Mulder calls Scully at the hospital to tell her about it; she in turn informs him that traces of an alien virus have been found in Gibson's body – anyway, he is partly an alien.

While Scully is distracted by Mulder's call, a Man with black hair kidnaps Price and takes him to the power plant to find and destroy the alien. Mulder catches up with them, but it's too late: they manage to lock themselves inside the reactor room. Mulder watches helplessly as an alien kills a Man with black hair. The alien turns to Price. At this time, the siren sounds, and FBI agents appear. Foley is now on Spender's side, she approaches Mulder and offers him to surrender.