If you were a fan of The O.C. back in the day, there's a pretty decent chance you've kept tabs on it's major stars throughout the years.
But while stars like Rachel Bilson moved on to Hart Of Dixie, and Ben McKenzie moved on to Gotham, it was some of the background characters on the hit show that made it *seriously* big in Hollywood later in life.
From Chris Pratt, to Lucy Hale, here are some of the epic celebrities who starred in minor roles on The O.C.
Chris Pratt as Che
The in-demand star of Jurrassic World and Guardians Of The Galaxy once played a supporting role on the tween drama, as Summer Robert's annoying, pretentious activist friend at college. Che wore a lot of knit cardigans, hats, and totally sold out Summer and got her expelled from Brown University.
Olivia Wilde as Alex
Olivia got her big Hollywood break in Orange County, as bad-girl bartender Alex who dated both Seth and Marissa.
Shailene Woodley as Kaitlin Cooper
The Big Little Lies star might be making it big in award winning dramas now, but back in 2003 she starred as the original Kaitlin Cooper in the first season of The O.C. She was later replaced by Willa Holland.
Lucy Hale as Hadley
The Pretty Little Liars alumn appeared in one episode in Season Three, as Kaitlin Cooper's boarding school roommate Hadley. She was *not* likeable.
Paul Wesley as Donnie
The Vampire Diaries star scored a role as the tough kid from the Crab Snack who befriended Ryan Atwood in Season One. He eventually shot Luke at a house party that got a *little* out of hand.
Amber Heard as Shop Girl
The actress played a snooty shop girl who accidentally (or, not so accidentally if you believe Summer) locked the gang in a mall overnight.
Jaime King as Mary Sue
She would later star in Hart Of Dixie for four years with Summer Roberts AKA Rachel Bilson, but in Season One of The O.C. she played Mary Sue. Her character convinced Seth Cohen to compete in a televised dance contest, after meeting at their Nanna's retirement home. Weird, but sure.
Bella Thorne as Young Taylor
She's all grown up and starring in films includng The Duff and The Babysitter, but once upon a time Bella acted as the innocent younger version of Taylor Townsend in a flashback scene.
Nikki Reed as Sadie Campbell
Nikki is the first of three Twilight stars who was first spotted on the show. She played Sadie, the cool cousin of Johnny Harper who dated Ryan Atwood for a little while.
Jackson Rathbone as Justin
He starred as Jasper in Twilight, but he previously broke our hearts as the adorable Justin, who tried to woo Kaitlin Cooper in the Fourth Season.
Cam Gigandet as Kevin Volchok
He starred as a villain in Twilight, and we don't need to tell you how he was in The O.C. Volchok was responsible for Marissa's untimely death and the world will never forgive him.
Ashley Benson as Riley
The Pretty Little Liars alum played popular girl Riley, who had a fight with Kaitlin Cooper in Season Four.
Max Greenfield as Young Sandy Cohen
He might be known for his hilarious alter-ego Schmidt from New Girl, but he also had a minor role playing a young Sandy Cohen in a flashback scene. With those brows and his lush hair, we can see why!
Jeffrey Dean Morgan as Joe Zukowski
His acting credits include Grey's Anatomy, P.S. I Love You and The Good Wife, but he once had a small role on the show. He played Joe Zukowski, a former friend of Sandy Cohen serving a jail sentence for manslaughter.