The O.C.was one of the most important teen dramas of the 2000s, and gave many aspiring young stars a promising head start. The show revolves around the lives of the residents of an upper-class neighborhood in Orange County, alternating between the grown-up’s relationships and their respective children, including Ryan, a troubled teenager with a rough background who is welcomed in the Cohen family’s residence.

IconicO.C.characterssuch as Seth, Ryan, and Summer launched the young actors to stardom, but outside the scope of main characters, the show introduced many smaller characters throughout its four seasons. Some fans might need a reminder of the movie stars that appeared in the show before their careers really kicked off.

Amber Heard

8Amber Heard

In one of her earliest roles,Amber Heardwas featured in a singleThe O.C.episode as a salesgirl in Season 2, Episode 15, “The Mallpisode.” As the title suggests, this episode features the main characters stranded in the mall when they happen to stay past closing time. Heard would eventually rise to prominence with roles such as Piper inDrive Angry, Miss San Antonio inMachete Kills, Ulla inThe Danish Girl, and the superheroine Mera inAquaman.

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7Shailene Woodley

Shailene Woodleykicked off her career so early that evenThe O.C.’s most hardcore fans might have not noticed she was the one who played Kaitlin Cooper in the first season of the show, just before Willa Holland took over the role. Woodley made her onscreen debut when was only eight years old in the TV movieReplacing Dad, landing a series of child roles in the 2000s. She’s now one of the most promising actresses in Hollywood, most commonly known for playing Hazel inThe Fault in Our Stars, Tris inDivergent, and Jane Chapman inBig Little Lies.

6Chris Brown

Before establishing himself as an R&B icon and a widely talented rapper,Chris Brownengaged in a series of small TV roles in the late-2000s, including shows such asAll of Us, The Suite Life of Zack & Cody, and, of course,The O.C.. Brown is introduced as Will Tutt in the second portion of the show’s fourth season in Episode 9, “My Two Dads”, appearing in three episodes in total. Will is a high-spirited member of the school band and becomes infatuated with Kaitlin, but he eventually realizes she is no good for him.

Brown stayed out of the radar for quite some time after aseries of legal issuesand controversies, but he still releases music and occasionally appears in TV shows, as was the case recently withBlack-ishandA House Divided.

Shailene Woodley

5Paul Wesley

Paul Wesleywas doing great in the 2000s as a regular in the showWolf Lake, then set out to make small, yet crucial appearances inSmallvilleas Lucas Luthor,Everwoodas Tommy Callahan, andThe O.C.as Donnie. Although he only appears in Season 1, Episode 5, “The Outsider”, his catastrophic actions are highly impactful to the following episodes. Donnie is introduced as an acquaintance of Ryan and is invited by Seth to a party. There, he makes inconvenient advances toward Summer, destroys the party host’s kitchen, and accidentally shoots Luke in the arm with a real gun.

In 2009, Wesley rose to prominence as Stefan Salvatore, one ofThe Vampire Diaries' most beloved characters. More recently, he took over the iconic role of James T. Kirk inStar Trek: Strange New Worlds.

cHRIS Brown The OC

4Max Greenfield

Max Greenfieldwas the chosen one for a rareThe O.C.flashback featuring the beloved couple Kirsten and Sandy Cohen. In Season 4, Episode 13, “The Case of the Franks,” fans get to see how the two lovelings met back in their college years. Greenfield is perfectly cast as Sandy, and their unique resemblance adds a nice touch to the scene.

His guest appearance happened in the same year he would get his breakthrough role as Nick Pepper inUgly Betty,and the actor would go on to play Schmidt inNew Girl, Dave inThe Neighborhood, and Joe inPromising Young Woman.

Paul Wesley THE OC

3George Lucas

Legendary film director and producerGeorge Lucasappeared in Season 2, Episode 23, “The O.Sea”, in one of the most exciting cameos in the show. At the peak ofThe O.C.’s most acclaimed season, Seth and Zach find themselves in a harrowing dilemma: one must take Summer to the prom, and the other needs to meet Lucas to discuss the future of their graphic novel. Seth is the one who ends up face to face with Lucas, who plays himself, and the two share an unusual mentor-and-pupil moment, prompting Seth to leave the meeting and enjoy the prom with his soul mate.

Thisunexpected cameo appearancein the show proves how influentialThe O.C.was at its peak. The episode came out in the same month as Lucas’Star Wars: Episode III - Revenge of the Sithand bringing the filmmaker to the show was a great way to promote it. Additionally, Lucas revealed to showrunner Josh Schwartz that his daughter was a huge fan of the show and talked him into it.

Max Greenfield

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2Olivia Wilde

Olivia Wildecaused quite a buzz with her character in the second season ofThe O.C., shaking the relationship dynamics of the show by seducing not only the fan-favorite Seth Cohen, but also the problematic Marissa. The actress played Alex, a recurring character introduced in Season 2, Episode 3, “The New Kids on the Block.” She’s a rebellious teenager who got emancipated from her parents, dropped out of school, and settled in Orange County with a job at the Bait Shop club.

Wilde is now a prolific movie star and filmmaker, best known for playing Quorra inTRON: Legacyand directing and starring inDon’t Worry Darling.

1Chris Pratt

Different from other guest performances inThe O.C.,Chris Prattwas among the ones who stayed the longest,appearing in nine episodesof the show. Introduced in Season 4, Episode 1, “The Avengers,” “Ché” Cook pretends to be a left-wing activist who advocates for good causes while he in fact is the spoiled kid of a wealthy pharmaceutical company owner. He becomes a vital part of Summer’s arc and his quirky personality is both hilarious and annoying: In one instance, Che is convinced by the mystical powers of his mind that Seth is his soul mate.

Pratt joinedThe O.C.’s final seasons shortly afterEverwoodended, in which he played Bright Abbott. His hilarious performance as Andy Dwyer inParks & Recreationwould eventually launch him into the mainstream, granting him the role of Owen Grady inJurassic Worldand Peter Quill inGuardians of the Galaxy.