Spanning eleven seasons and 218 episodes, The X-Files ranks third in the list of longest running Sci-fi shows of all time. The character with the most appearances on the show was Fox Mulder. who was a main character in the first seven seasons and a recurring character in the eighth and nine seasons. Mulder would later return as the main protagonist in the series reboot.

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The paranormal activities investigator was portrayed by David Duchovny in both the original series run and the revival. For his role as Mulder, Duchovny twice received Emmy nominations for "Outstanding Lead Actor in a Drama Series." Here are a couple of things you didn't know about the FBI Special Agent.

His First Words As A Baby

clyde bruckman's final repose

Mulder's first words were "JFK." He said the words when he was 11-months-old. This detail was revealed in the seventeenth episode of Season 4 titled "Musings of a Cigarette Smoking Man."

This episode marked the first time in which Mulder didn't appear at all. However, his voice was heard during a secret meeting. The plot revolved around an author who went back in time, where he was tasked with assassinating President Kennedy. As Mulder's team discussed the author, they revealed his first words as a child.

He Appeared In The Simpsons

Fox Mulder Simpsons

Animated versions of Mulder and Scully appeared in The Simpsons. The two were featured in the tenth episode of Season 8 titled "The Springfield Files." In the episode, a freaked out Homer Simpson reported an alien sighting, so Mulder and Scully came to town to investigate it.

However, Mulder and Scully couldn't find any evidence of alien activity, making people think Homer was a liar. Homer thus ended up being ridiculed by residents in the neighborhood. The episode also had several references to the X-Files, including the Speedo and The Smoking Man.

Aliases Used

Fox Mulder Meets John Doggett in The X-Files

Mulder often needed to remain anonymous when conducting investigations. In order to identify the real culprits that were associated with paranormal activity, he couldn't risk going the Bond route by introducing himself as "Mulder, Fox Mulder."

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He used a couple of aliases such as "Marty Mulder." He used this alias for the first time in the seventh episode of Season 2 titled "3." He used it again in the twentieth episode of Season 4 titled "Small Potatoes." However, Mulder preferred the more discreet "George Hale" whenever he needed to hide his identity.

How The Role Was Cast

The X-Files' FBI Agents Scully and Mulder in promo shot

Lance Guest was the first actor to audition for the role of Fox Mulder. However, casting director Randy Stone really wanted to see David Duchovny as Mulder, so he asked him to audition for the role.

Duchovny eventually got the part. He went on to star in every season of the FOX series. Lance Guest was later cast as a minor character, appearing in the Season 2 episode titled "Fearful Symmetry. Younger versions of Mulder were portrayed by Marcus Turner and Nick Lashaway.

Key Numbers In His Life

Mulder in The X-Files

According to Fox Mulder's FBI employee profile, his work phone number was (202)555-9355, while his cell phone number was 555-3574. His badge number was JTT 047101111, whereas his identification number was 2219-526. His date of birth was listed as October 13, 1961.

He weighed 170 pounds while his height was 6'0'. The profile also listed his Smallpox vaccination number as 292544. Mulder's lost sister also had an X-File case which was X-42053.

Preferred Outfits

Scully and Mulder in The X-Files

Keen viewers might have noticed that Mulder had a very specific dress code. In all of the character's appearances in the series, he wears one of three different sets of outfits.

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His first wardrobe choice is a black suit with a white shirt and black tie. His other choice is a yellow t-shirt that has the words 'Robinson's Diner' written at the front in a red font. The t-shirt also has a food image. Mulder's third wardrobe choice is a black FBI coat with a woolen hat, coupled with black pants.

Romantic Interests

The X-FIles Fight Club

Mulder's first partner was Scotland Yard agent Phoebe Green, who he hooked up with during his time at the Oxford University. Sadly, she cheated on him, forcing him to leave her and return to the United States.

In the pilot episode, it was revealed that FBI Special Agent Diana Fowley. The two began a relationship and it is during their time together that they discovered the X-Files. And after being partners for several years, Mulder and Scully began seeing each other. The two later had a child named William.

His Apartment Number

Mulder and Scully in The X-Files

Mulder's apartment number was 42. This is a reference to the popular Douglas Adams sci-fi series "The Hitchhiker's Guide to the Galaxy." According to the series, 42 is the answer to life and the universe. His full address was 2630 Hegal Place Alexandria, Apt.#42, VA 23242.

Mulder's most notable neighbor was Scott Ostelhoff. He lived in the apartment right above his and often spied on him through a hole in the ceiling. It was later revealed that Ostelhoff was an agent for The Syndicate. Mulder eventually found out that Ostelhoff was spying on him and killed him with a shotgun.

Choice Of Weapons

Fox Mulder pointing a gun in the X Files series.

When investigating paranormal activity, one has to be well-armed. You never know what kind of weapons aliens are resistant too, so the safe bet is to carry the best weapons.

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During his early years at the bureau, Mulder's choice of weapon was the Taurus 92 automatic rifle. When the risk levels increased significantly, he switched to a Glock 19 and a Sig Sauer 226. He kept alternating between the two for a while. And in the final seasons, he began using a Smith & Wesson 1076.

His Favorites

Fox Mulder and Scully in X-Files

Mulder's preferred beverage for stakeouts was the Iced Tea 35. His favorite genre of music was Classic Rock while his favorite movies and TV shows to follow were those of the sci-fi genre, specifically those released before 1960. He loved pornographic material too. He was seen going through the Celebrity Skin magazine on a few occasions and watching Adult Video News.

His favorite sports were basketball, football and baseball. He used to play baseball as a child, with his favorite position being the right field. He also stated that his favorite basketball team was the New York Knicks. As for football, his preferred NFL team is the Washington Redskins. He even used Redskins tickets to bribe Danny Valodella for adoption record searches.

NEXT: 5 Things Fringe Did Better Than The X-Files (& 5 Things X-Files Did Better)