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27 Actors You Probably Didn't Realise Were Guest Stars On Your Fave Shows

TFW you're binge-watching an old show and see your fave before they were famous.

We recently asked members of the BuzzFeed Community which actors they've been surprised to learn were in certain TV shows. Here are the best responses.

1. Zac Efron — Firefly


"Zac Efron as the young Simon in Firefly." —littlebrowndoggy

2. Dylan Minnette — Grey's Anatomy


"Dylan Minnette (Clay from 13 Reasons Why) was in Grey's Anatomy." —aylar3

3. Jennifer Lawrence — Monk

USA Network

"I was watching old Monk reruns and someone in a lion mascot costume walks into the locker room and takes off the head, only to reveal Jennifer Lawrence is underneath! She's even referred to as Jen!" —idyemyhairalot

4. Chris Hemsworth — The Saddle Club


—Klara Dvorak, Facebook

5. Zooey Deschanel — Frasier


"Zooey Deschanel as Roz's snarky and hipster cousin on Frasier! Not only is a blonde Deschanel bizarre, her too-cool-for-school attitude couldn't be more different from Jessica Day." —brookev44d349812

6. Aaron Paul and Jane Lynch — The X-Files


"Playing (respectively, in the same episode) a high school stoner and a high school principal. AMAZING." —caroliner4f34a2a95

7. Andrew Garfield — Doctor Who


"Andrew Garfield in Doctor Who. I rewatched that episode one day and was like holy shit... that's him." —stevenlegits

8. Steven Yeun — The Big Bang Theory


"Steven Yeun aka Glenn from The Walking Dead on The Big Bang Theory as Sheldon's old roommate." —616489

9. Millie Bobby Brown — NCIS


"Millie Bobby Brown (Stranger Things) played a sociopath who killed her mother on NCIS." —KT Phillips

10. Emma Stone — Malcolm in the Middle


"Blew my mind seeing Emma Stone in an episode of Malcolm in the Middle." —Tor Harbin, Facebook

11. Ryan Gosling — Goosebumps


"Ryan Gosling on Goosebumps! 'Say Cheese and Die'!" —cumberbabe1395

12. Joe Manganiello — One Tree Hill

The CW

"Whenever anyone starts talking about Joe Manganiello being on True Blood or Magic Mike, I like to remind them that we had him first as Owen on One Tree Hill." —DeAnna Hall, Facebook

13. Gabriel Macht — Beverly Hills 90210


"Seeing Gabriel Macht from Suits on Beverly Hills 90210 was probably the most cool yet WTF moment of my entire life!" —quadryillduce

14. Rami Malek (from Mr Robot) — Gilmore Girls

Warner Bros

—Ian Vicencio

15. Ethan Suplee and Adam Scott — Boy Meets World


"Adam Scott as Griffin Hawkins and Ethan Suplee as Frankie Stechino, Cory's bullies, in Boy Meets World." —b47d45633e

16. Courteney Cox — Murder She Wrote


"Courteney Cox in Murder, She Wrote! Makes me laugh every time I see her." —Hanna McGrath-Perdue, Facebook

17. Zach Braff — The Baby-Sitters Club


"Zach Braff in 'Dawn Saves the Trees'." —DeAnna Hall

18. Max Greenfield — The OC


"He was young Sandy Cohen on The OC!" —Denise St. Pierre, Facebook

19. Matthew McConaughey — Unsolved Mysteries


"I was very surprised to find out Matthew McConaughy was in an episode of Unsolved Mysteries. I had to go back and rewatch the episode (it's on the DVD set). It's so weird to see, yet he does a great job in such a sad story. I remembered the story, but when I first saw it I clearly had no idea that he would become such a famous renowned actor." —laurelc3

20. Shia LaBeouf — Freaks and Geeks


"Honestly, I was surprised by everybody who appeared on Freaks and Geeks but seeing little Shia LaBeouf as the injured mascot will always surprise me. Still so cute and so hilariously Shia even all the years ago." —serinaholguin

21. Amy Adams — Charmed


"Watching old episodes of Charmed and Amy Adams pops up playing a good samaritan who is tapped by a 'dark lighter' demon that makes her so unlucky she wants to jump off a building. Thankfully she is saved by the Power of Three and lives to become an Oscar-nominated actor. Phew!" —alvarof4f1bc732e

22. Nick Offerman — The West Wing


"Nick Offerman (Ron Swanson) had a cameo in The West Wing long before Parks and Recreation! He played Jerry (yes Jerry!) in the Season 1 episode 'The Crackpots and These Women'." —pavlovabunny

23. Mila Kunis — 7th Heaven

The WB

"Mila Kunis on 7th Heaven as Lucy's frenemy Ashley, before she was on That '70s Show." —stephaniemedina56

24. Jeremy Piven — Seinfeld


"Jeremy Piven from Entourage auditioning and getting the role of George in the pilot of 'Jerry' in Seinfeld." —Dean Nye

25. Lin Manuel Miranda — How I Met Your Mother


—Jocelyn May, Facebook

26. George Clooney — The Golden Girls


"George Clooney played a cop on The Golden Girls." —Liz Boccolini

27. Evan Peters — The Office


"Evan Peters as Michael Scott's nephew in The Office. I couldn't stop laughing when he got spanked in front of the entire staff." —Stephanny Paz, Facebook

If you want to be featured in future BuzzFeed posts, make sure to follow the BuzzFeed Community on Facebook and Twitter.

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