The Cleaner (The X-Files)

In The X-Files television show, the Men in Black (MIB for short, and singular, Man in Black) refer, unofficially, to a group of enforcers employed by the Syndicate to execute assassinations, cover ups and other covert operations. It is implied that most, if not all, of them are former members of special operations units. Some, mostly shown in comedic episodes, parodied the traditional view of MIBs from UFO lore. Most had no known civilian identities, though there were some exceptions. They rarely speak.

The Men in Black are analogous to the alien bounty hunters employed by the Colonists. The Men in Black were, however, not as reliable as the bounty hunters for difficult tasks. They were sometimes used initially, but it often took the more capable Alien Bounty Hunters to complete these missions. However, the Syndicate would use the bounty hunters only when necessary because of an increased risk of exposure.

As of the series finale, it is assumed they have been phased out, as the "New Syndicate" (Super Soldiers) does not have as great a need to employ normal humans.

X is portrayed by Steven Williams. X was a high-ranking member of the Men In Black (MIB), a group of operatives used by The Syndicate to carry out their dirty work. X first appeared at the beginning of season 2, after he contacts Mulder to tell him he "has a friend at the FBI." X became Fox Mulder's information source, replacing Mulder's first informant, Deep Throat, who had been murdered at the end of season 1. X is a subordinate of The Smoking Man.

While X's loyalties and his own agenda were often unclear, he has more than once proven that he at least does not want Mulder dead. In the episode "End Game", he is approached by Dana Scully, who pleads that she needs to know where Mulder is, believing his life to be in danger. Initially X refuses, and is subsequently confronted by Walter Skinner, who seemed to recognize X. He relinquishes Mulder's location, though not until after a brief but intense scuffle with Skinner. In the episode "731", X's loyalty to Mulder is further confirmed. Trapped on a train car equipped with a time bomb, Mulder, about to escape, is attacked brutally by an MIB assassin. X fatally shoots the Red Haired Man as he is about to step off the car. X boards the car with only enough time left to save either Mulder or the alien-human hybrid the car was transporting, opting to save Mulder, and carries him off to safety just as the car explodes.

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