The X-Files was one of the most definitive series of the ’90s, full of cynical conspiracies and serialized stories. Being such a cultural phenomenon, it’s no wonder that so many celebrities passed on through. Many actors utilize smaller television roles as stepping stones towards leading positions.

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It’s always a welcome surprise to revisit an older show and spot an early appearance by famous actors. Often, it isn’t just because of a familiar face. Their talent and charisma set them apart since that’s what led to their recognizable career after all. So, here are ten of the best cameos we ever had on this iconic, moody and compelling show.

Adam Baldwin

Jayne Cobb looking surprised in Firefly

Here’s a fun character actor that you’ve probably seen all over the place. Proud nerds will identify him from Firefly, but many could also recognize him from Full Metal Jacket. He generally plays some variant of a militaristic tough guy, with a cocky attitude and gravelly voice. But there’s no denying that it’s a lot of fun to see him reprise it, every time.

In this case, he was a marine with Doggett, and he gets to play a supersoldier. So, Baldwin’s few cameos tie him deeply into the mythology arc of the show, which is always entertaining. He fits the role more than he molds it, but it’s always welcome because he has plenty of recognizable personality.

Terry O’Quinn

Terry O'Quinn Lost John Locke

You’ll probably recognize O’Quinn best from Lost, the J.J. Abrams hit that loved to torture him. Locke was a perpetually tragic character. That isn’t quite the case for O’Quinn’s varied appearances on The X-Files. That’s right—he didn’t have just one cameo. He had multiple roles, all of which were different!

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And yet, there is literally zero connective tissue among each of the appearances. It’s pretty startling, and perhaps a tad confusing. In fact, O’Quinn even showed up in the 1998 movie. He brings a very natural quality to his roles, which often ask for exaggerated traits. And yet, he is able to ground them, even on a show that has monsters every single week.

Giovanni Ribisi

Somehow, Ribisi is a guy that manages to sell the ability to control lightning, without coming off cheesy. The idea itself is somewhat unimaginative, but the execution is largely entertaining. And thanks to Ribisi’s convincing performance, it’s even pretty intriguing. He takes on the role of a slacker teen, alongside a friend played by Jack Black.

However, Black basically does his thing. Ribisi is commonly known for a majority of comedic roles, and that isn’t the case here. He really captures the epitome of an awkward, angsty teen. He comes off legitimately disturbed, and his quiet moodiness is surprisingly intimidating.

Laurie Holden

Laurie Holden XFiles

Whatever your thoughts on The Walking Dead these days, there's no denying that it's still an absolute juggernaut. And for a while, it was even a legitimate phenomenon. This is attributable to its killer first season, where Holden played "Andrea" and quickly loses her sister.

Truthfully, the role probably could have gone to any talented actress, since Andrea is just an everyday woman. But Holden's position in The X-Files feels more fitting. She played Marita Covarrubias over a few episodes, spanning two seasons. That mysterious character frequently had unclear motivations, acting on one side or another. It's revealed that she works for the Syndicate. Although she eventually opposes the Syndicate, Holden really captured the shadowy charisma as their representative.

Joe Morton

There is no question that you will remember this actor best for his role as Miles Dyson, in Terminator 2: Judgment Day. It's so iconic, he essentially reprised that role for the DCEU as Cyborg's father. Further, he ends up in another story about time travel right here in The X-Files. It certainly can’t be a coincidence.

His character begins to experience time in reverse after his wife's murder. It’s a jarring situation even for audiences to keep track of. Morton always does a great job of selling panic and desperation. That’s because Morton also brings his signature everyman charisma.

Michael Emerson

Michael Emerson Arrow Villain

Here’s yet another actor that you’ll recognize from Lost. Emerson frequently plays characters that are on the strange side. Which is odd, since he generally has a friendly face. He utilizes that harmlessness throughout Person of Interest. But for some reason, he can really sell the crazy. Enough to convince you that he truly was evil in Saw. And this time, he certainly plays an awkward, creepy guy. But only because he’s so obsessed with The Brady Bunch.

Audiences might have been dismayed that the show went for such a comedic episode right before the series finale itself. However, it’s a fun breather and the premise is a lot of fun, even if you could care less about Cousin Oliver.

Bruce Campbell

Only Bruce Campbell could possibly portray such a sympathetic Demon. And how ironic, given that he is best known for battling demonic possessions as Ash from The Evil Dead franchise. But all Campbell’s character wants in this bizarre episode is to become a father.

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The catch is, he wants a normal baby, so he kills any offspring with demonic traits. And ultimately, he’s not even the worst Demon of the episode. Campbell is allowed to play a more subdued role, surprisingly. He doesn’t have to be so manic or desperate, and it absolutely works. It’s easy to have genuine empathy for his Demon.

Luke Wilson

Luke Wilson XFiles

"Bad Blood" is actually the highest-rated episode of the entire series. Which is curious, since the entirety of it is unabashed comedy. One might think that fans would prefer one of the horror pieces. However, Wilson's episode allows Mulder and Scully to recite events from their unique points of view.

So, they get to rib each other in a knowing way, that lets fans in on the joke. Everyone who understands these characters is rewarded. In the middle of our protagonists' playful bickering is Luke Wilson. He alternately gets to perform an idiotic stereotype with large crooked teeth, and a charming everyman. He gets two cameos in one, and he nails both of them.

Bryan Cranston

Bryan Cranston in the X-Files

Cranston is easily one of the strongest working actors on the planet. Every single episode of Breaking Bad proved it. He can inspire sympathy or understanding for even the greatest villainy. It's no wonder Vince Gilligan hired him for Walter White. Cranston's cameo is yet another desperate man, with a constant, sharp sound in his head.

In fact, it could literally make his head explode—it killed his wife. Ultimately, he takes Mulder hostage, so plenty of the episode is escalating drama in a car. It's safe to say that without Cranston, this episode would actually suffer greatly.

Brad Dourif

Brad Dourif The X-Files

This is truly one of the most stunning episodes of the entire show. You’ll know Dourif best as the voice of Chucky himself, from the Child’s Play franchise. It’s a real shame that Hollywood decided to make one without him. His maniacal laughter and playful menace are undeniably charming for horror fans. But in The X-Files, Dourif has more of a Lecter-esque role.

He plays a psychic who claims he can connect with Scully’s father, from the afterlife. The episode digs into those phenomena with sincerity and intrigue. Dourif’s knowing superiority is a lot of fun, and his abilities are remarkably convincing.

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