On a hiking trip in North Carolina, a young woman has a vision of being trapped in a cave of yellow goo. The couple's skeletons are found oddly preserved in a field, and Mulder notes how it's near a UFO hotspot; Scully thinks it's a double murder with ritualistic themes involving the stripping of flesh from the body. Scully finds some yellow goo on the bodies, which tests positive for a digestive secretion with plantlike characteristics. She has a sample forwarded to the FBI. Mulder goes to the place the bodies were found and sees one of the missing hikers alive; he pursues him into a cave, where the hiker tells him their deaths were faked by aliens and his wife is still abducted. Scully visits the field, but doesn't find Mulder. A bright light floods the cave and the hiker's wife is returned; she also says they were abducted.
Mulder thinks the incident is one of textbook alien abduction, though he can't explain the skeletons. The light returns, and Mulder goes toward it. Cut to Mulder's apartment, where Mulder has apparently gone after leaving Scully in North Carolina. She arrives, surprised to find the married couple there, as well as an alien that Mulder has himself abducted. Scully is flabbergasted, but surprised when Mulder is skeptical of her reaction and still questioning the idea that the skeletons are decoys. He also sees visions of the yellow goo, and turns out to be in a cave full of it.
Scully and the coroner find the goo in the field, as well as a new skeleton whose dental records match Mulder. The coroner's theory on what killed him is the same as Scully's original one...word for word. She's now skeptical of that explanation. A wake is held at Mulder's apartment, where The Lone Gunmen promise to launch their own investigation but say they concur with the ritualistic murder theory. Scully thinks something else is going on, and starts to have yellow goo visions of her own. Mulder arrives at the apartment, and suddenly everything is back to normal.
Mulder gives his abduction story, and Scully assures him the hikers are dead and points out a few more gaps in his story. Scully thinks they're in a hallucination of some sort, with its origin in the field, and recalls the wild mushrooms there that gave off spores. She now thinks the couple was dissolved by a giant carnivorous hallucinogenic fungus, and the realization is enough for them to escape the cave. At least until they give their final report, and Mulder realizes they shouldn't have been able to will themselves out of the hallucination. He shoots Skinner to prove to Scully that they're not yet in real life, and Skinner bleeds yellow goo. Luckily, non-goo Skinner is leading a team of agents on a rescue mission, and Mulder and Scully are finally pulled to safety.
David Denman, who plays Wallace Schiff, also played Roy Anderson on the American version of The Office. Jim Beaver, as a coroner, played Whitney Ellsworth on Deadwood.
Episode Body Count
Angela and Wallace Schiff: their skeletons are found embracing in a field three days after they go missing, digested by the giant fungus.
Two past cases: the coroner remembers two prior cases of skeletal remains found in the same area.
Cumulative Body Count (138/202 episodes, 1/2 movies)
Humans: 1,552Creatures: 104
Grand Total: 1,718