The X-Files is an American science fiction drama television series created by Chris Carter, which originally aired from September 10, 1993 to May 19, 2002 on Fox.

The X-Files follows the careers and personal lives of FBI Special Agents Fox Mulder (David Duchovny) and Dana Scully (Gillian Anderson). Mulder is a talented profiler and strong believer in the supernatural. He is also adamant about the existence of intelligent extraterrestrial life and its presence on Earth. This set of beliefs earns him the nickname "Spooky Mulder" and an assignment to a little-known department that deals with unsolved cases, known as the X-Files.

Agent Scully is a foil for Mulder in this regard. As a medical doctor and natural skeptic, Scully approaches cases with complete detachment even when Mulder, despite his considerable training, loses his objectivity. She is partnered with Mulder initially so that she can debunk Mulder's nonconforming theories, often supplying logical, scientific explanations for the cases' unexplainable phenomena.

Walter Skinner is portrayed by Mitch Pileggi. Skinner is an FBI assistant director who served in the United States Marine Corps in the Vietnam War. During this time he shot and killed a young boy carrying explosives, an incident which scarred him for life. Skinner is originally Mulder and Scully's direct supervisor.  Although he is originally portrayed as somewhat antagonistic, he eventually becomes a close friend of Mulder and Scully.

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