Substance: It is hard to avoid the suspicion that (in the real FBI) Mulder and Scully would have been exiled to play with the X Files because they are totally incompetent as investigators. SEMI-SPOILER-ALERT, if you haven't seen the series yet.
(1) Since someone in the government is engaged in a deep cover-up of paranormal events (shown in the episodes), why not just destroy all the X files in the first place, OR prevent Mulder from working on them with the excuse that he is more needed elsewhere.
(2) Once the skin marks and nasal insert are known, the failures to check for additional evidence by (a) exhuming all the corpses, before they are stolen; (b) check the two living subjects, while they were in the hospital with them; plus (c) not securing the evidence, instead of leaving it in a motel room unguarded lead inexorably to the charge in the opening paragraph.
(3) The "solving" of the case, as put forth by the agents, was nonsensical dialogue.
OK, I'll admit to being spoiled by NCIS and Sherlock (this was an early TV series), but it doesn't even rise to the level of Twilight Zone.
Style: Pretentious suspense, poor dialogue, muddy characterization. OH, and running the director's "extra" before the show was a pain for us who had not yet seen it. Poor form. ( )