Darlene Morris has taken her two kids camping. Quite unfortunately, her daughter gets abducted by aliens. While it's not "there is a spider in the toilet" bad, it's still pretty bad.
Worst camping trip ever.
When Scully finds out that Mulder is eager to go investigate, it turns out that the incident is pretty close to what happened to his sister. It also comes up that Darlene Morris witnessed a UFO when she was a Girl Scout.
When they visit Darlene, Mulder watches as her son Kevin writes what appears to be binary code. He says it comes from the staticky TV. Everyone resists the urge to make Poltergeist jokes, and Mulder takes a few pieces of paper to analyze. While that's going on, they also discover that the missing girl Ruby was a troublemaker who had run away before, and her friend Tessa says Ruby was pregnant and planned on running away with her boyfriend Greg.
That night, the NSA arrives to knock down Mulder and Scully's doors. Kevin's code is part of a satellite transmission, and when Scully tells them the source, they ransack the Morris house and drag the poor kid away. HI HO GOVERNMENT, AWAY.
The usual fate of creepy children.
Mulder and Scully return to the scene of the abduction. Sand has been turned to glass, and Mulder insists it indicates a massive heat source. It's aliens, not lightning. Remember that. Then wolves appear, and they follow them to a shallow grave: Ruby's boyfriend. A note in his wallet leads them back to Tessa, who admits in interrogation that she is actually pregnant, and killed Greg. She has no idea where Ruby is, though.
When they return to the Morris house, Mulder spreads out Kevin's papers and realize that the "binary" actually makes a picture of Ruby's face. Back at the lake, they find Darlene and Kevin in the woods. Also, a wild motorcycle gang appears, but they aren't actually relevant at all. What is relevant is Ruby, also asleep in the woods. She is dehydrated and in a coma. Mulder notes that her symptoms are similar to what astronauts experience in low gravity.
Ruby says that she was told not to say anything about her experience, and Darlene refuses to let Mulder question her further, fearing her daughter will endure the same mockery she did. Mulder leaves, dejected, no closer to understanding what happened to his sister.
And, presumably, preparing for Confession.
While it wasn't directly related, I do love that they gave a little hint to the overall arc, with Ruby being cautioned to say nothing by an unknown group.