FBI's Criminal Investigations Division. In 2000, Alvin Kersh assigned him to the X-files unit as Scully's partner after an unsuccessful task force attempt to find Mulder. He does not appear in The X-Files feature films. Monica Reyes is portrayed by Annabeth Gish (season 9; also starring season 8; guest seasons 10–11):Reyes is an FBI special agent who was born and raised in Mexico City. She majored in folklore and mythology at Brown University and earned a master's degree in religious studies. Her first FBI assignment was serving on a special task force investigating satanic rituals. She is a longtime friend of Doggett's and becomes his partner after Scully's departure. She did not appear in The X-Files feature films. Walter Skinner is portrayed by Mitch Pileggi (season 9–11; also starring seasons 3–8; recurring season 2; guest season 1):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. He later serves the same position for Doggett and Reyes. Although he is originally portrayed as somewhat antagonistic, he eventually becomes a close friend of Mulder and Scully. He appeared in an episode of The Lone Gunmen and in both The X-Files feature films. Also starring Cigarette Smoking Man is portrayed by William B. Davis (seasons 4–7, 9; recurring seasons 1–3, 10–11):The Cigarette Smoking Man is the series' primary villain. In the ninth-season episodes "William" and "The Truth", it is suggested that he is Mulder's biological father. In the seventh-season episode "Requiem", he is believed to have been killed after being pushed down a flight of stairs by Alex Krycek until the ninth-season finale "The Truth", in which Mulder and Scully travel through remote New Mexico and reach a pueblo where a "wise man" reputedly lives, who is revealed to be Cigarette Smoking Man. He also appears in the 1998 feature film. Alex Krycek is portrayed by Nicholas Lea (seasons 5–9; recurring seasons 2–3; guest season 4):Krycek is a Russian-American, the son of Cold War immigrants, and first introduced as an FBI Special Agent assigned as a temporary investigation partner to Fox Mulder. Krycek proceeds to work with Mulder and attempts to gain his trust. However, it later becomes evident that Krycek is actually an undercover agent working for