Supernatural has come a long way since season one — fifteen years to be exact! It's easy to keep track of where actors like Jared Padalecki and Jensen Ackles are as they both still play the two main characters of the show, but it's not difficult to wonder what everyone else has been up to for the past decade and a half.

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Some found success, and some even wound up back on the show. Regardless, the "classic" Supernatural cast set the standard for all the following actors who would appear and collectively played an important role in making the show the success it is today.

Brendan Fletcher

He delivered one of the best performances of the season, and possibly the series, as Max Miller, the troubled young man from an abusive home who turns out to be one of the yellow-eyed demon's psychic children. Although Max dies within the episode, as the first of the psychics the Winchesters encounter, his plot sets up Sam's story during the next season.

He may have only been a one-off in Supernatural, but Brendan has since held recurring roles in iZombie, Arrow, and, most recently, Siren. He certainly has come a long way since 2006 and undoubtedly has great things in his future.

Megalyn Echikunwoke

Another talented actress who proved herself within a single Supernatural episode, Megalyn played Cassie Robinson, a love interest of Dean's in "Route 666." Cassie is known among fans as Dean's first love, but it's Megalyn who instilled the character into Supernatural history.

In 2015-16, she voiced the leading role in the animated CW Seed series, Vixen. As the show was part of the Arrowverse, she also played the live-action version of her character, Vixen, aka Mari McCabe, in an episode of Arrow. Her biggest role to date, however, came earlier this year as Edie Palmer alongside Brittany Snow and Emily Osment in FOX's Almost Family.

Gillian Barber

Supernatural fans may know her better as season twelve's Dr. Hess, but eleven years before her British Men of Letters role, Gillian Barber played Mrs. Rourke in "Faith." Her daughter, Layla, is in line to be cured of her cancer by a reverend healer, but when the reverend chooses to heal Dean instead, Mrs. Rourke's spite is enough to send a shiver down all our spines.

Gillian has played Deidra Peck in Hallmark's Chesapeake Shores, and has also had a recurring role in Amazon's The Man in the High Castle alongside DJ Qualls, another Supernatural alum!

Loretta Devine

Having been in the film industry since the 1980s (and on Broadway even before that), Loretta Devine was no stranger to the screen when she starred in "Home" as Missouri Moseley, a psychic who helps Sam and Dean rid their childhood home of a vengeful spirit.

She has since had roles in movies like Death at a Funeral and For Colored Girls and television shows like Black-ish and The Carmichael Show. But perhaps her most memorable performance was as Adele, Dr. Webber's wife, in Grey's Anatomy, for which she won Emmy. Loretta also returns to Supernatural in season thirteen's "Patience," and although she dies in the episode, her death sets up the story for her granddaughter Patience Turner's entrance into the show.

Taylor Cole

When Sarah Blake became the first woman since Jess to steal Sam's heart, she stole the hearts of fans as well. Although the two are clearly attracted to each other, Sam chooses not to go back to her town after wrapping up the case. She returns for one episode in season eight and reveals that she has a husband and daughter before she is killed.

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After season one, she went on to star in episodes of Heroes, CSI: Miami, and CBS' Salvation. She has recently found success in a number of Hallmark originals, playing the leading roles in the Ruby Herring Mysteries and One Winter Weekend movies.

Tyler Johnston

Before he was the angel Samandriel in season eight, Tyler Johnston played Matt in the episode that would come to live in infamy, "Bugs." He brings a charm to an otherwise questionable episode as a boy who takes interest in the patterns of his neighborhood insects whose knowledge helps Sam and Dean solve the case of the swarms plaguing the town.

Tyler has starred in the independent film-turned-series The Age of Adulting and the Kyra Sedgwick-directed Story of a Girl. He is currently a series regular on Letterkenny, which has just been renewed for an eighth season.

Nicki Aycox

She brought about the original portrayal of the demon Meg, a role that Rachel Miner would take over in season five. Both actresses are praised for their sultry, sarcastic portrayals of the character, but Nicki is credited with iconicizing the role, putting Meg on the map and etching her into the Supernatural history books.

Although she had roles on Cold Case and TNT's Dark Blue, some of Nicki's newest work includes her 2015 album Red Velvet Room, a five-song EP.

Adrianne Palicki

She plays a sweet, supportive girlfriend to Sam in the show's pilot, which makes her death at the end of the episode that much more poignant. Although she doesn't spend a lot of time on screen, Adrianne's character Jess, and Sam's grief about her death is essentially what kickstarts the plot of the entire show.

In 2011, before Gal Gadot's record-breaking version of Wonder Woman hit the big screen, Adrianne was set to lead her own Wonder Woman series, following Lynda Carter's 1979 show. The production didn't get far, but Adrianne found success elsewhere on hit shows like Friday Night Lights and Marvel's Agents of S.H.I.E.L.D. She currently stars as Kelly Grayson in Fox's The Orville, which has recently been renewed for a third season.

Samantha Smith

Like Jess, Samantha's character was also killed in the pilot of the show. It's Mary's death that steers her husband John onto his path of vengeance and into the hunting life, taking his sons with him. She made occasional appearances as dream versions of Mary, and even once as Eve, the mother of all monsters in the Supernatural universe, in season six.

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She makes a more permanent return to the show, however, in the last seconds of season eleven when Amara resurrects Mary. Her latest run spans until Mary's death occurs as recently as last season. Fans speculate this to be her final appearance, but in a show where people are coming back from the dead left and right, there is really no telling who will be returning for the final season.

Jeffrey Dean Morgan

Fans have voiced strong opinions about John Winchester over the years, but almost everyone can agree that JDM's performance was phenomenal and played an important role in the foundations of the series. He returned to the show briefly in season fourteen's "Lebanon," but he had several roles before and after.

Coming up on the tail of his time in Supernatural was his part as Denny Duquette in Grey's Anatomy, followed by recurring roles in shows like Extant and The Good Wife, but he is probably better known for playing Negan in The Walking Dead.

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