10 Famous Actors Who Appeared on It’s Always Sunny in Philadelphia Before They Were Famous

Paul Walter Hauser – “Dee Reynolds: Shaping America’s Youth” (Season 6)

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Before stealing scenes in I, Tonya and earning critical acclaim in Richard Jewell, Paul Walter Hauser played Richie — a misfit student mentored by Charlie. Dressed in Juggalo makeup and full of angst, his character is both hilarious and oddly heartfelt.

Jaimie Alexander – “Underage Drinking: A National Concern” (Season 1)

Jaimie Alexander, best known as Lady Sif in Marvel’s Thor franchise and as the lead in Blindspot, made one of her first TV appearances as a high schooler dating Dennis. Her role in the show's first season hinted at a bright future ahead.

Judy Greer – “The Gang Runs for Office” & “Frank Sets Sweet Dee on Fire”

Judy Greer is one of Hollywood’s most beloved character actors, with roles in Ant-Man, Arrested Development, and Jurassic World. She guest-starred twice on Always Sunny as Ingrid Nelson, a former classmate who’s now a successful designer — and completely uninterested in reconnecting with the gang.

Pablo Schreiber – “A Very Sunny Christmas” (Season 6)

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Long before his lead role as Master Chief in Halo or his breakout in The Wire, Pablo Schreiber showed up in It’s Always Sunny’s only Christmas special. He plays Ricky Falcone, the victim of Mac’s childhood holiday thefts — and the target of a hilariously half-hearted apology.

Alexandra Daddario – “Charlie and Dee Find Love” (Season 8)

Before leading roles in True Detective and Baywatch, Alexandra Daddario played Ruby Taft — a sweet, wealthy woman who briefly falls for Charlie. The twist ending is classic Sunny, and Daddario nails the contrast between charm and chaos.

Jimmi Simpson – Liam McPoyle (Recurring Character)

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Of all the early roles of famous actors on Always Sunny, Jimmi Simpson’s Liam McPoyle might be the most iconic. He’s since starred in Westworld and Black Mirror, but fans of Sunny still remember him for the eye patch, unibrow, and milk-drinking madness.

Retta – “The Gang Gets Extreme: Home Makeover Edition” (Season 4)

Before playing Donna Meagle on Parks and Recreation, Retta appeared as a hardware store clerk helping Charlie and Dennis plan a wildly misguided home renovation. It’s a quick scene, but her comedic presence stands out — even surrounded by Sunny’s madness.

Jimmy O. Yang – “Flowers for Charlie” (Season 9)

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Before gaining fame on Silicon Valley and Space Force, Jimmy O. Yang had a brief role on It’s Always Sunny as a scientist monitoring Charlie’s supposed rise to genius. His scene in “Flowers for Charlie” shows early signs of the comedic talent that would soon make him a star.

Nasim Pedrad – “The Waitress Is Getting Married” (Season 5)

SNL alum Nasim Pedrad had a short but sharp role as a bridal shop clerk in season 5. Her character quickly calls out Dee’s lie about getting married, adding a dose of grounded sarcasm to a typically unhinged episode.

Tiffany Haddish – “Charlie Gets Crippled” (Season 2)

Tiffany Haddish, now a powerhouse in comedy with roles in Girls Trip and Night School, appeared as a stripper in the episode that introduced Danny DeVito’s Frank Reynolds. It's a blink-and-you'll-miss-it role, but it's a fun part of her early acting career.

Final Thoughts

These Famous Guest Stars on Always Sunny Might Surprise You

As one of the longest-running sitcoms in TV history, It’s Always Sunny in Philadelphia has had plenty of time to feature rising talent. These now-famous actors used the show as a stepping stone — and in some cases, delivered unforgettable early performances.

So next time you rewatch an old episode, keep your eyes peeled. You never know which future A-lister might show up at Paddy’s Pub.