X (The X-Files)

X
The X-Files character
First appearance	"The Host"
Last appearance	"The Truth"
Created by	Chris Carter
Portrayed by	Steven Williams Natalija Nogulich (deleted scenes)
Information
Gender	Male
Occupation	FBI Agent
Affiliated with	Men in Black Federal Bureau of Investigation, The X-Files
Duration	1994–1996, 2002

X, sometimes referred to as Mr. X, is a fictional character on the American science fiction television series The X-Files. He serves as an informant, leaking information to FBI Special Agents Fox Mulder and Dana Scully to aid their investigation of paranormal cases, dubbed X-Files. The character serves as a replacement for Deep Throat, who had been killed off in the first season finale, "The Erlenmeyer Flask". X himself would be killed off after appearing in several seasons, eventually being replaced by Marita Covarrubias.

X is portrayed in the series by Steven Williams, and made his début in the second season episode "The Host", although the character would not appear on-screen until "Sleepless", two episodes later. The role had originally been conceived as female, with Natalija Nogulich cast in the role; however, her initial scenes were deemed unsatisfactory by the producers, leading to her replacement. Williams' portrayal of X was intended to introduce a personality completely different to the character's predecessor, Deep Throat, and has been positively received by critics and fans.

The character of X was originally intended to be a woman, and Natalija Nogulich had been cast in the role. However, Nogulich was replaced by Steven Williams after shooting her first scene, as the writing staff felt Nogulich was not able to create the "right chemistry" with her co-stars. Williams had previous experience with writers Glen Morgan and James Wong, although it was series creator Chris Carter who suggested him for the part.

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