Through its 15 seasons on The CW, Supernatural has welcomed dozens of celebrities onto the show in small roles, many of which are huge favorites among genre fans. However, many celebrities appeared on the fantasy series that no one could have expected to show up. Throughout the decade-plus, Sam and Dean Winchester have teamed up with, saved, and defeated characters played by celebrities from every walk of life.

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Not only have some very familiar faces shown up on Supernatural, but there have also been some young actors who appeared on the show before breaking out big time years later. One day a young actor is killed by a wilderness creature, and just a few years later, they are headlining their own TV show or movie. Here is a look at 10 actors you forgot were on Supernatural.

AMY ACKER

person of interest amy acker root

When Supernatural came on The CW, it replaced a very popular vampire series in Angel. While plenty of Angel fans initially boycotted the new horror television series, it smartly played into the fanbase and brought a handful of characters from the Buffyverse onto the show in guest roles. The first was Amy Acker, who portrayed Fred on Angel.

This was the season 1 episode "Dead In The Water" as Andrea Barr. She was the mother of a young boy who found himself in danger when a malevolent ghost returned to the town where he was murdered, seeking vengeance of the two people who killed him by targeting their families.

PARIS HILTON

paris-hilton-supernatural

Out of every celebrity that appeared on Supernatural, the one that seemed least likely was debutante Paris Hilton. The heir to the Hilton fortune and party girl extraordinaire was in a season 5 episode titled "Fallen Idols." The episode saw three super fans meet their idol, Paris Hilton, only to have her kidnap one of them.

It turned out that Paris Hilton was the demon Leshi, who assumed the identities of famous people to kidnap and sacrifice their fans. The best part for fans who hate these pseudo-celebrities was that Sam beheaded Paris Hilton/Leshi with an ax.

LINDA BLAIR

Linda Blair Posessed in The Exorcist

If there is any actor who brought true horror legacy to Supernatural, it is Linda Blair. For those who don't know, Blair was the iconic actress who, as a child, portrayed Regan in The Exorcist. The demonically possessed little girl gave the nation nightmares for years as she vomited pea soup and said things a child should never hear.

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On Supernatural, Blair was on the other side of good and evil. She portrayed Diana Ballard, a police detective in the season 2 episode "The Usual Suspects." She arrests Sam and Dean when she realizes who they are, but ends up as their ally by the end.

LAUREN COHAN

Lauren Cohan in Supernatural

The world of horror television fell in love with Lauren Cohan as she portrayed the tough-as-nails Maggie Walsh on the AMZ zombie series The Walking Dead. Cohan had a small recurring role on Supernatural in Season 3 before her starring turn as a zombie killing heroine.

On Supernatural, she was a woman who sold her soul to a Crossroads Demon and spent the next few years as a hustler who stole objects and sold fake charms to wealthy clients. When her deal with the demons came to an end, she struck a deal to work for them to steal The Colt from the Winchesters but ended up facing her hellhound in the end.

JULIE BENZ

Julie Benz as Rita Morgan in Dexter

Fans of both Buffy the Vampire Slayer and Angel know Julie Benz as the evil vampire who turned Angel and held control over him for many years. She also got a second life on television when she appeared on Dexter as his love interest Rita. On Supernatural, she was one of the first season guest stars from the Buffyverse.

Benz starred in the episode "Faith" as a woman in a small town with cancer named Layla. Dean and Sam arrived in town because Dean was dying, and Sam heard there was a faith healer there. The preacher saved Dean, which angered Layla's mother because her daughter never got her turn. When it turned out the preacher used a captured Reaper, Dean and Sam had to stop him before he could save Layla.

ASHLEY BENSON

Ashley Benson Supernatural

Ashley Benson became a star thanks to her role in the hit ABC Family series Pretty Little Liars. However, before she took on the part of Hanna Marin on that series, Benson appeared in a small role in an episode of Supernatural. The episode was season 4's "It's the Great Pumpkin, Sam Winchester."

Benson starred as Tracy Davis, a 600-year-old witch who raised a demon named Samhain with her brother Don. The Winchester brothers thought she was a victim and saved her when her brother tried to sacrifice her but then learned that raising a demon had its downfalls.

ADRIANNE PALICKI

Agents of SHIELD Adrianne Palicki Mockingbird

Adrianne Palicki became a huge fan favorite for geek genre television after she appeared on the very first episode ever of Supernatural. While she was an unknown at the time, Palicki starred as Jessica Moore, Sam's college girlfriend who ended up dad and burning on the ceiling, sending Sam back into his hunting ways.

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Palicki also returned in season 5 when Lucifer disguised himself as her. Fans got to know Palicki well in her roles in the FX series Legion, the hit comedy sci-fi series The Orville, and as the recurring of Mockingbird on Marvel's Agents of S.H.I.E.L.D.

ALDEN EHRENREICH

Alden Ehrenreich as Han Solo and Rogue One

When it comes to actors who appeared on Supernatural as a nobody before breaking out huge, none fit that description better than Alden Ehrenreich. The young actor appeared in the first season episode "Wendigo" as Ben Collins. While Cory Monteith was the bigger star in the following years, thanks to Glee, it was Ehrenreich that had the most prominent future role.

Ehrenreich gained more popularity when he appeared in the young adult fantasy movie Beautiful Creatures. He proved how good he was in some critically acclaimed films like Chan-wook Park's Stoker, Woody Allen's Blue Jasmine, and The Coen Brothers' Hail, Caesar! However, his most significant role by far was as Han Solo in Solo: A Star Wars Story.

RICK SPRINGFIELD

Supernatural lucifer season 12 rick springfield

In the '80s, Rick Springfield was a pop music star with the hit song "Jessie's Girl." However, what many people may forget is that he was also an actor at the time. Around the same time that he was winning a Grammy for that song, he was also a regular actor on the daytime soap opera General Hospital.

In season 12, Springfield started acting again. He portrayed a rock star named Vince Vincente for three episodes. More importantly, he was a vessel of Lucifer.

CHARISMA CARPENTER AND JAMES MARSTERS

spike sitting in chair james marsters buffy the vampire slayer

The biggest guest stars on Supernatural to come from the Buffyverse appeared in the same episode. The episode was in season 7 and was titled "Shut Up, Dr. Phil." In that episode, James Marsters and Charisma Carpenter starred as a pair of witches named Don Stark and Maggie Stark.

Of course, Marsters and Carpenter portrayed Spike and Cordelia on both Buffy the Vampire Slayer and Angel. In this episode of Supernatural, they were often-bickering old witches who ended up living at the end up allowed to live once the Winchester boys help them realize they still love each other.

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