Jensen Ackles, Jared Padalecki, and Misha Collins in a Supernatural promo photo

Supernatural has been on television for many, many years at this point (some may say too many years, but that's an argument for a different day). Its longevity has made it one of the most popular shows on The CW and has allowed it to take its main characters through adventures all across the world (and many other worlds). The Winchesters' adventures have grown in intensity and ridiculousness over the years, somehow getting too unbelievable at times for a fake ghost hunting show. (Side note: remember when they were still worried about demons? Good times.)

It has also allowed the show to pick up hundreds of guest stars. Because of its popularity within the horror genre, popular horror stars have made stops on the show, while other stars who had not yet become famous made appearances while getting prepared for stardom. Here are 17 Stars You Forgot Appeared On Supernatural.

17. Alden Ehrenreich

Alden Ehrenreich Supernatural

The soon-to-be young Han Solo was a young angsty teen in his appearance on Supernatural, playing the younger brother of a hiker who disappeared in the woods in the show's second ever episode. Ehrenreich's character and his sister go into the woods with the Winchesters to search for their big bro, and eventually find him and save him from being eaten by a Wendigo. The role was the up-and-coming actor's first ever appearance. Since then, he has gone on to star in Beautiful Creatures, Stoker, Blue Jasmine and Hail, Caesar! with many more roles to come. He is set to become an even bigger name soon with appearances in Rules Don't Apply and The Yellow Birds and a much hyped starring role as the younger version of Harrison Ford's Han Solo in an upcoming Star Wars film. Another actor who appeared in Ehrenreich's Supernatural episode? The late Cory Monteith of Glee, playing another one of the Wendigo's victims.

16. Adrianne Palicki

Adrianne Palicki Supernatural

Adrianne Palicki played Sam's ill-fated college girlfriend Jess, who was subjected to the same fate as the brother's mom in the pilot episode of the series, burned to death by the mystery demon who spurred the whole Winchester hunting lifestyle. Most Supernatural fans remember Jess, since she was such an integral piece of the series, but many forget that the actress who played her has gone on to become so well-known. Palicki got her start appearing on shows like Supernatural, South Beach and Lone Star before landing the lead role of Tyra Collette on beloved high school football series Friday Night Lights. After the series ended, she starred in Keanu Reeves' John Wick, played Wonder Woman in a failed NBC pilot and had a recurring role on About A Boy. She is better known to comic book fans for her role as Bobbi Morse on Agents of S.H.I.E.L.D. While the character is popular, numerous discussions of a spin-off series have not come to fruition. Palicki can next be seen in the upcoming TV mini-series Pretty Vacant and series Orville.

15. Bellamy Young

Bellamy Young Supernatural

Scandal star Bellamy Young had a blink and you'll miss it appearance on Supernatural's fifth season. Although her character Sarah was only around for a short time, she had a huge impact on the series. Young appeared in a flashback that showed how Mark Pellegrino's Nick came to accept the challenge to be Lucifer's vessel. Young's Sarah was Nick's wife who was murdered during a home invasion but returned, possessed by Lucifer and ready to convince Nick to make a very important decision. Young, who graduated from Yale University, is well known for playing the president's (now ex-) wife and current presidential candidate Mellie Grant on the ABC series Scandal. Before she landed the role, she appeared on shows like Criminal Minds, Scrubs, Knight Rider, Two and a Half Men, Trust Me, Dirty Sexy Money, Private Practice, Boston Legal, Grey's Anatomy, CSI: Miami, Medium, Peacemakers, American Dreams and more. She also appeared in films like Mission Impossible: III, We Were Soldiers and Simple Things. Most recently, she appeared in The Nigth Stalker.

14. Titus Welliver

Titus Welliver Supernatural

Multi-talented long-time actor Titus Welliver appeared on Supernatural's fifth season as the Horseman War. He was vanquished by Sam and Dean, who took the ring he needed to focus his powers, but the horseman did put up an impressive fight. Welliver will be recognizable to most film and TV fans, with a wide variety of different appearances in different types of media. In film, he is well known for appearing in thrillers and action movies like The Town, Transformers: Age of Extinction, Air Force One, Assault on Precinct 13, RED 2 and Argo. In TV, he has had guest starring roles on The X-Files, Nash Bridges, The Practice, Star Trek: Voyager, Law & Order: SVU, The Twilight Zone, Numb3rs, Jericho, NCIS, Prison Break, Monk, Grimm, Agents of S.H.I.E.L.D., White Collar, The Mentalist and The Last Ship. He also has had recurring or starring roles on Deadwood, Lost, Suits and The Good Wife. He is currently starring as the title character on the Amazon series Bosch.

13. Leslie Odom Jr.

Leslie Odom Jr. Hamilton

Tony Award winner Leslie Odom Jr. took his charismatic ways to Supernatural, although on the show, he was using his charm for evil. Odom played a crossroads demon named Guy who liked to take in victims while posing as a reunion planner. Aside from just being regular demon evil, Guy is extra bad because he likes to renege on his deals early. Odom will be familiar to savvy TV fans from his many guest starring roles; the actor has appeared on shows like Law & Order: Special Victims Unit, Person of Interest, Smash, House of Lies, and CSI: Miami in recurring roles and shows like The Good Wife, Gotham, Grey's Anatomy and Gilmore Girls for just one episode. However, Odom is best known to theater fans for his appearances in multiple Broadway shows, most notably smash hit Hamilton. Odom first appeared on Broadway in Rent but eventually rose to theater and national fame through his role as Aaron Burr, which earned him a Tony for best actor and a Grammy for the cast album.

12. Emmanuelle Vaugier

Emmanuelle Vaugier Supernatural

Emmanuelle Vaugier's appearance on Supernatural is probably remember by most fans as one of the more tragic early episodes of the series. It was season two, and Sam was still reeling from the death of his college girlfriend Jess when he met Vaugier's Madison, who had been unknowingly turned into a werewolf by her neighbor. Madison's life just keeps getting worse as she kills her boyfriend while in her werewolf state, and, despite a budding romance with Sam, she ends up asking the hunter to kill her so that she won't hurt anyone else. Sam and Madison really hit it off, as evidenced by the fact that, in season four's alternate reality episode "It's a Terrible Life," he tells Dean that Madison is his fiancé. Aside from breaking Sam's beautiful little heart on The CW series, Vaugier is also familiar to fans of the Saw series for her appearance in Saw II and can be seen in CSI: NY, Smallville, Two and a Half Men, Covert Affairs, Secondhand Lions, 40 Days and 40 Nights and, more recently, Lost Girl.

11. Ashley Benson

Ashley Benson Supernatural

Ashley Benson is a 26-year-old who can play both a high schooler and a 600-year-old witch, as she proved during her appearance on Supernatural. Although the actress is best known for playing high school student Hanna Marin on the ABC Family/Freeform series Pretty Little Liars, about to head into its eighth and final season, on Supernatural, she played someone much older, appearing as witch Tracy Davis. Davis, masquerading as a high school student, is able to trick Sam and Dean into killing her warlock brother for her, allowing her to raise Samhain, one of the 66 seals that would allow Lucifer to rise all the way back in season four. Outside of the mega-popular Pretty Little Liars, Benson has also appeared in Days of Our Lives (her appearances were years after Supernatural star Jensen Ackles left the show), Bring It On: In It To Win It, Eastwick, Spring Breakers, How I Met Your Mother, Family Guy, Pixels, Chronically Metropolitan and Pretty Little Liars spin-off Ravenswood. Benson is also very popular on social media, with over four million followers on Twitter and over 14 million followers on Instagram.

10. Tricia Helfer

Tricia Helfer Supernatural

Tricia Helfer is well known to nerds everywhere for her famous sci fi roles and various guest appearances, including a stop on Supernatural in season two. Helfer played Molly, a woman who keeps on returning to the same tragic night where she and her husband accidentally struck and killed a man with their car. Molly also died in the crash, unbeknownst to her, but luckily, Sam and Dean are around to help her let go of her emotional baggage (something they clearly know a lot about) and move on to a better place. Helfer is best known for playing Cylon Number Six on Battlestar Galactica, a role which catapulted her to stardom when the series was released in 2004. Building off of her success, Helfer booked recurring guest roles on Burn Notice, Dark Blue, Two and a Half Men and more, and also appeared on shows like Chuck, Warehouse 13 and Human Target. Helfer recently appeared in her own short lived series, Killer Women, and can be seen in the upcoming season of Lucifer as the devil's mother.

9. Meghan Ory

Meghan Ory Supernatural

Once Upon a Time's Meghan Ory appeared on a season seven episode that fans will probably remember more as their first introduction to tiny hunter Krissy, a teen who Sam and Dean mentored after her father went missing. Ory played Sally, a Vetala monster who was responsible for Krissy's father's fate, which the teen didn't react well to. Ory has experience acting on shows featuring supernatural creatures. One of her first roles was on the TV series Vampire High, where she played human lead Sherry Woods. She is best known for playing Red Riding Hood (real life name: Ruby Lucas) on Once Upon a Time, although she has not been a series regular since the second season. Outside of the two shows, she also starred opposite Lost's Josh Holloway for one season of the CBS thriller Intelligence and can be seen in The Memory Book, Dead Rising: Watchtower, Chesapeake Shores, Psych, True Justice, Dark Horse, John Tucker Must Die, Sanctuary and Blond and Blonder.

8. Aldis Hodge

Aldis Hodge Supernatural

Aldis Hodge appeared in Supernatural's second season as one of the other super powered children left with a lifetime of mental scars courtesy of the demon Azazel. Hodge played Jake Talley, the former soldier who Sam met while at the creepy camp that Azazel made for the kids. Talley came out victorious in Azazel's murder game, only to be killed by Sam trying to stop the opening of the Devil's Gate. Hodge has been acting since he was young, first appearing in Die Hard with a Vengeance. His next big role was the recurring part of Ray 'Voodoo' Tatum on Friday Night Lights before he hit it big by landing the part of nerd and go-to computer whiz Hardison on TNT's Leverage. After the show ended, he returned to the Die Hard series with A Good Day to Die Hard and had guest starring roles on The Walking Dead and Justified before landing a recurring role on TURN: Washington's Spies. Recently, he has been seen in Straight Outta Compton and the WGN America series Underground. He is set to star in Hidden Figures and Jack Reacher: Never Go Back.

7. Snooki

Snooki Supernatural

Jersey Shore star Nicole "Snooki" Polizzi appeared as a version of herself in a season nine episode, playing an alternate Snooki who is actually functioning as a vessel for a crossroads demon. Sam and Dean question her about Crowley before exorcising her and leaving Snooki free to go back to the shore, with Dean commenting that her being a demon "makes so much sense." Aside from Jersey Shore and its spin-off Snooki and Jwoww, Polizzi has also appeared on Dancing with the Stars and has been a guest host for WWE Raw. Another reality show who has stopped by Supernatural? Paris Hilton, who reunited with her House of Wax co-star Jared Padalecki in a season five episode. Like Polizzi, Hilton, who is known for being a socialite and for starring in The Simple Life, played a version of herself, this time as a wax figure brought to life by people idolizing her and other celebrities.

6. Sterling K. Brown

Sterling K. Brown Supernatural

Recent Emmy winner Sterling K. Brown played Gordon Walker on Supernatural, a hunter who had a thing for killing vampires, no matter what it took. His harsh ideas put him at odds with Sam and Dean, and, when he was eventually turned into a vampire himself, Sam was forced to decapitate him. Although Brown was done on Supernatural, his career was just beginning. The actor went on to appear in Our Idiot Brother and guest star on shows like Medium and The Good Wife before landing the role of Detective Carter's boyfriend Cal on Person of Interest. He then began playing a series regular role on Lifetime's Army Wives and guest starred on NCIS, The Mentalist, Castle and Criminal Minds. He also recently appeared in Tina Fey's Whiskey Tango Foxtrot and is part of the cast for NBC's This Is Us. Brown has been receiving the most buzz recently, though, for his appearance as Christopher Darden in Ryan Murphy's The People v. O.J. Simpson: American Crime Story. The role recently earned him a Primetime Emmy for Outstanding Supporting Actor in a Limited Series or Movie.

5. Linda Blair

Linda Blair Supernatural

Linda Blair hit the big time early on in her career, earning an Academy Award nomination and a Golden Globe win for her appearance in the horror flick that would define all future horror flicks, The Exorcist. Supernatural owes much of its success and popularity to the horror films and shows that came before it, so it makes sense that the show would invite scream queen Blair to make an appearance. Blair appeared in a season two episode as a detective who arrests Sam and Dean but eventually comes around to their claims about ghosts. Supernatural is one of Blair's only recent roles; since then, she only has five IMDb credits. She did make an appearance on a 2012 episode of Celebrity Ghost Stories, and has also been featured as herself on Pit Boss and RuPaul's Drag Race. She is also known for reprising her Exorcist role in the 1977 sequel and for appearing in films like Hell Night, Chained Heat, Savage Streets and Scream.

4. Jason Dohring

Jason Dohring Supernatural

Veronica Mars bad boy Jason Dohring appeared in a season seven episode as Chronos, the god of time—which makes sense considering that Dohring basically looks exactly the same now as when he played a high schooler on the WB series in 2004. The actor played the god of time in a season seven episode featuring Supernatural's version of famous police man and leader of The Untouchables Eliot Ness, played by The X-Files' Nicholas Lea. Chronos doesn't make it past the end of the episode, but his premonitions do serve as the first hint for season eight's Leviathan storyline. Outside of Veronica Mars, Dohring has also appeared on Moonlight, Party Down, Ringer, The Messengers and The Originals. He has also voiced Terra in the Kingdom Hearts video game series, and has appeared in films like Deep Impact, Portrait of Love, The Squeeze and Destined. He is set to appear in the upcoming Cleveland., about a struggling writer in New York, with Lucy Fry, Amber Tamblyn and Jackie Cruz.

3. Candice King

Candice Accola King Supernatural

Candice Accola King started off on a very different supernatural show before landing her role as Caroline Forbes on The Vampire Diaries. King appeared in a season four episode as a love interest for Brock Kelly's young Dean when he and Sam (Colin Ford) spent a few weeks at a high school while their father worked on a job. King's Amanda Heckerling didn't have a long relationship with Dean, breaking up with him when she found out he was two-timing her with another girl (you know, emotionally damaged Dean Winchester stuff), but it profoundly affected him, with the brooding hunter remembering the encounter years later when he and Sam go back to investigate a haunting at the school. King, though, had to move on to her own angst, taking a role on The CW's The Vampire Diaries, which is headed into its eighth and final season. Outside of the show, she has also appeared on How I Met Your Mother, Greek, Drop Dead Diva and Dating Rules From My Future Self. She also has a budding music career.

2. Sarah Shahi

Sarah Shahi Supernatural

Sarah Shahi appeared in Supernatural's very creepy pilot episode as the ghost Constance Welch, a woman driven to murder her children and then kill herself after finding out that her husband cheated on her. Her dramatic death turned her into a vengeful spirit who goes around the town finding cheating men and killing them, much to the chagrin of Sam and Dean, professional ghost hunters. Shahi went on from Supernatural to starring roles on The L Word and Life before moving on to headlining her own series Fairly Legal. After its cancellation, she appeared in Bullet to the Head, Road to Paloma and Chicago Fire before landing the role of Sameen Shaw on Person of Interest, which she played through the series' recent finale. She was recently cast as the lead in CBS' dark, adult Nancy Drew reboot, titled Drew, but the network declined to pick up the pilot. It was shopped around and, according to IMDb, is now set to be released as a TV movie at some point later this year.

1. Most of the Buffy-verse

Buffy Angel Firefly Stars Supernatural

Supernatural has featured a whole lot of people from your favorite Joss Whedon shows. The first to appear was Amy Acker (Fred on Angel; Whiskey on Dollhouse), who showed up as a mother trying to save her son from a creepy ghost trying to drown people. Next up was Julie Benz (Darla on Buffy and Angel), playing a terminally ill woman who Dean prevents a faith healer from saving because it would violate his very strong Winchester moral compass (which is a thing, apparently). Then comes Amber Benson (Tara on Buffy), who first appeared in a season two episode before popping up again in season six as Lenore, a vampire who has sworn off of human blood. Then comes Mercedes McNab (Harmony on Buffy and Angel), also playing a vampire. Season seven of Supernatural ended up being Buffy-verse central. First up to appear was Jewel Staite (Kaylee on Firefly) as a Kitsune who Dean befriended as a child but is later forced to kill. Then came the wonderful duo of Charisma Carpenter (Cordelia on Buffy and Angel) and James Marsters (Spike on Buffy and Angel), who played a dueling couple of ancient witches. Rounding out the season of Buffy appearances was Harry Groener (Mayor Wilkins on Buffy), a professor who helps Sam and Dean solve a case involving a group of Amazons. Another former Buffy star who you probably haven't forgotten appeared on Supernatural (although you may have forgotten she ever appeared on Buffy) is Felicia Day, who played Sam and Dean's nerdy helper Charlie on the series and also appeared as one of the potential slayers on Buffy's seventh season. Day also starred in Whedon's Dr. Horrible's Sing-Along Blog.