The X-Files: 10 Best Characters Who Appeared After Season One

Donald "Donnie" Pfaster was Scully's greatest fears made manifest. Donnie was a "death fetishist", which sounds terrifying just by itself. He would collect hair and nails from dead people, mostly women, thanks to his job as a funeral home assistant.

When Donnie got fired from his job because it turned out defiling the dead isn't looked at positively, he decided to use his natural charisma to attract women to him so he could kill and mutilate them.

When Scully arrived to help the investigation, Donnie instantly targeted her, even kidnapping and attempting to kill her near the end of their first encounter.

Donnie chased Scully around his house for several minutes, and the unarmed agent could only struggle to try and escape the man. Eventually, Donnie was put in jail by Scully, only to be set free by another deranged serial killer.

It was in this second encounter that Scully learned the truth about Donnie. It turns out he was never an actual human being at all, but in fact, a real-life demon from hell.

Donnie's initial appearance, and the implication that any human could become so evil, was what truly scared audiences and Scully back in the much more innocent time of the 1990s, even if he was then retconned into being a literal demon.