who is part of the cast?
Robert Patrick, Annabeth Gish and Gillian Anderson.
Improbable (The X-Files)
The show centers on FBI special agents who work on cases linked to the paranormal, called X-Files; this season focuses on the investigations of John Doggett (Robert Patrick), Monica Reyes (Annabeth Gish), and Dana Scully (Gillian Anderson). 
what is improbable from the x-files? It is the thirteenth episode of the ninth season of the series "The X-Files". what is the plot? In this episode, Reyes and her fellow agents investigate a serial killer who uses numerology to choose his victims. Soon, Reyes and Scully meet an unusual man who may prove more of a hindrance than a help.
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Improbable (The X-Files) [SEP] Introduction
The show centers on FBI special agents who work on cases linked to the paranormal, called X-Files; this season focuses on the investigations of John Doggett (Robert Patrick), Monica Reyes (Annabeth Gish), and Dana Scully (Gillian Anderson). In this episode, Reyes and her fellow agents investigate a serial killer who uses numerology to choose his victims. Soon, Reyes and Scully meet an unusual man who may prove more of a hindrance than a help. "Improbable" features Burt Reynolds playing God. Reynolds was chosen after he expressed his desire to appear in an episode of "The X-Files" to Robert Patrick. Carter approved the idea, and Patrick later said that Reynolds enjoyed filming the episode.