Mulder and Scully investigate the strange deaths of members of a high-school graduating class in the Pacific Northwest.
Returning to the scene of their first investigation seven years ago, Mulder and Scully encounter a UFO that may spell the end of their partnership.
A seemingly unstoppable Billy Miles begins killing scientists performing genetic research – then targets Scully.
Mulder searches for answers when a connection is made between Billy Miles and members of the FBI; Scully and Reyes find refuge in a remote location as Scully prepares to give birth.
After Mulder is put to rest the body of an alien abductee comes back to life, giving Scully and Skinner cause for hope.