A beautiful woman with the ability to remain submerged underwater infiltrates the FBI.
A man, Carl Wormus, intrigues a woman in a bar by mentioning that the government is adding chloramine to the water supply. They go for a drive together but as they near a drawbridge the woman grabs the steering wheel sending them plunging into the water. She grabs his ankle to stop him escaping.
Monica Reyes meets up with Assistant Director Follmer in his office. Follmer hands Reyes two videos which contain footage of the underground garage where Doggett and Skinner fought off "super soldier" FBI agents. But the video shows nothing out of the ordinary.
Meanwhile, at a water reclamation facility, a worker is pulled underwater by the woman from the bar.
Doggett shows up at Scully�s apartment to tell her that Mulder isn�t living in his apartment anymore. Scully already knows but refuses to elaborate further.
Skinner urges Doggett to drop his investigations. Scully agrees but Doggett tells her his supposed friend, Knowle Rohrer, had tried to kill him and Skinner in the garage.
Doggett gets home and finds a photograph of him and Rohrer in the marines so decides to find out about Rohrer. Coincidentally, the woman from the bar, Shannon McMahon, is also in the photo.
McMahon sneaks into the FBI and leaves an envelope containing Wormus� obituary. Doggett pursues the lead by calling Scully into the morgue where she determines that Wormus drowned but notes the bruising on his ankle.
The Lone Gunmen tell Reyes that Doggett and Skinner left to investigate emails sent to Carl Wormus from a worker at the water plant named Roland McFarland - the man Shannon McMahon drowned. Doggett and Skinner sneak into the main control room where Doggett finds files relating to chloramine. Follmer tracks the men but Doggett slips into a filtration tank to get away.
Suddenly Shannon McMahon surfaces and grabs hold of Doggett and pulls him under the water.
To be continued...