Attorney Jay Cassal finalizes Skinner's divorce petition. Skinner, however, decides to wait one more day before signing the document.
     While relaxing at the Chesapeake Lounge at the Ambassador Hotel, Skinner is approached by an attractive woman. The pair strike up a conversation, and their apparent mutual attraction and loneliness quickly escalates to lovemaking in a hotel room. During their passion, Skinner sees the woman change from an attractive lover to an old woman. Skinner suddenly awakens. When he turns to the woman from the bar, he discovers her lifeless corpse.
     Scully and Mulder join Homicide Detective Waltos at the crime scene, where they learn details about the murder and Skinner's possible involvement. The victim is identified as Carina Sayles, a former legal secretary who moonlighted for an escort service. The agents interview Lorraine Kelleher, who runs the escort service. Kelleher states that Sayles called her from the bar and used Skinner's credit card number to pay for the "transaction."
     Scully tells Mulder neither of them really knows very much about Skinner's personal life. Later, the agents meet with their boss after he is released from jail. But he is uncooperative, and refuses to comment about the incident, or explain why he refused a polygraph test. During their conversation, it dawns on Mulder that Skinner did not know that Sayles was a prostitute.
     Scully shows Mulder a videotape containing footage of people who suffer from REM sleep behavior disorder. The affliction causes sufferers to grow violent during sleep, perhaps explaining the murder. Scully learns from Skinner's psychiatrist that he had been experiencing a recurring dream in which he is confronted by an old woman. Mulder links the description to a succubus, a spirit that visits men during the night in just such a form.
     Skinner's wife, Sharon, pays a visit to Skinner's apartment. Later, police discover that Sharon was involved in an automobile accident-and evidence that someone ran her off the road. All evidence points to Skinner. Later, Skinner tells Mulder he first encountered visions of the old woman during a near-death experience in Vietnam.
     Mulder searches Skinner's damaged car for clues. He cuts away the automobile's exploded air bag from the steering wheel and has it analyzed. The FBI crime lab constructs a computerized image of a facial imprint embedded in the air bag. It belongs to someone other than Skinner. Mulder suspects that someone within the government is trying to destroy Skinner (having failed in their attempts to kill him in a previous episode).
     A hearing is established to investigate the facts in the case. Skinner's accusers use Scully's testimony about the X-Files to dismiss him from the Bureau. Later, the agents discover that Kelleher fell from her condo high-rise. They question her assistant, Judy, who identifies the computer image of the man who stole Skinner's car as the same man who hired Sayles to approach Skinner. The agents arrange for Judy to meet the suspect at the Ambassador.
     Skinner visits his ailing wife at the hospital. There, he again sees the image of the old woman, who beckons to him from his wife's bed. Skinner moves closer, only to see Sharon's form. Sharon whispers something in Skinner's ear.
     The man who's image was reconstructed from the air bag surprises Judy and Scully in their hotel room. Mulder and Detective Waltos rush to their aid, but Skinner mysteriously appears and guns down the assailant. When Scully asks Skinner as to how he knew the assailant's whereabouts, he cryptically declines to answer.