He is contacted by Agent Mulder to locate Dr. Baker, a Gregor being hunted by the alien bounty hunter. Special Agent Weiss is able to locate Dr. Baker but meets his demise by being exposed to the corrosive green blood of the alien bounty hunter. He is found dead inside the trunk of his own car. Later, in an autopsy room Scully reads through Weiss' autopsy report and finds his blood work shows polycythemia, an excessive production of red blood cells. She tells Mulder that Weiss' blood was "curdled like jelly, as if something cause the blood to thicken or clot prior to death."