‘It’s Always Sunny in Philadelphia’ Season 18 Cast Guide: Every New and Returning Face at Paddy’s Pub

Paddy’s Pub is back open for business, and the gang has brought some familiar faces along with a few unexpected ones for the ride. ‘It’s Always Sunny in Philadelphia’s‘ eighteenth season premiered simultaneously on FXX and FX on August 17, 2026, consisting of ten episodes. With the show now deep into its fifth decade on air, fans have plenty of reasons to track exactly who is walking through Paddy’s front door this time around.

The season stars Charlie Day, Glenn Howerton, Rob McElhenney, Kaitlin Olson, and Danny DeVito as “the Gang.” Beyond the core five, Season 18 leans hard into nostalgia, pulling back several beloved side characters while sprinkling in some genuinely surprising guest turns that have fans buzzing across social media.

The Core Gang Returns for Season 18

Charlie Day is back as the wonderfully weird Charlie Kelly, the former co-owner, janitor, and “rat basher” of Paddy’s Pub who has been making fans laugh since the very first episode. Besides starring, Day also serves as a writer and executive producer on the sitcom, and this season sees Charlie thrown into new antics involving tent encampments, workplace automation, conspiracy theories, and even a dead woman’s inheritance.

Kaitlin Olson also returns as Deandra “Sweet Dee” Reynolds, the Gang’s only female member, who remains just as hilariously toxic and self-absorbed as everyone else. Interestingly, Olson’s real-life husband is her co-star Rob Mac, formerly known as Rob McElhenney.

‘It’s Always Sunny in Philadelphia’ was created by Rob McElhenney, Glenn Howerton, and Charlie Day, and the trio continues to anchor the show alongside Olson and DeVito as their antics wreak havoc on everyone around them. Danny DeVito returns as the wildly unpredictable Frank Reynolds, and he is already at the center of one of the season’s craziest storylines involving his engagement to his Golden Bachelor love interest.

McPoyle Family and Old Favorites Make a Comeback

Season 18 brings back several deep cuts for longtime viewers. Older characters who have not appeared in recent seasons make a comeback, including the McPoyle family, longtime rivals of the Paddy’s Pub crew, made up of Liam played by Jimmi Simpson, Ryan played by Nate Mooney, and Pappy played by Guillermo del Toro.

Also back in their eccentric roles are David Hornsby as Rickety Cricket and Sandy Martin as Mrs. Mac. Several members of the McPoyle family reunite with the gang specifically at the Renaissance Faire, a setting that plays a major role in the new season’s chaos.

The del Toro cameo in particular has drawn attention from critics. His return appearance is being called one of the funniest and most unexpected cameos on any series, proving that the show’s pitch black humor appeals to everyone from average viewers to Oscar winning filmmakers. It’s a fun reminder that ‘It’s Always Sunny in Philadelphia’ has always attracted an eclectic mix of talent willing to disappear into its grimiest supporting roles.

New Guest Stars and Wedding Chaos Storyline

The biggest new addition to the cast conversation is Carol Kane. Frank has found love with Sam, played by Carol Kane, whom he met while competing on ‘The Golden Bachelor’ in a crossover episode last season, and the two are getting married at Paddy’s Pub. Much to Dennis and Dee’s delight, Sam is rich and generously offers to leave them money as her new stepchildren.

That storyline does not stay lighthearted for long. The trailer for the new season showed the death of Kane’s character Sam, a wealthy poultry heiress and fiancée of Frank Reynolds, marking a forty year reunion for both Kane and DeVito that ultimately leads into a chaotic wedding sequence.

On top of the returning faces, the season also introduces a fresh comedic cameo. The gang is joined by guest actors throughout the season, including Big Mouth comic Nick Kroll, who cameos in a Renaissance Faire episode. FXX has teased that viewers should brace for some of the series’ most outrageous moments and star cameos yet, noting that the Gang may be into their fifties and eighties now, but their behavior is more out of control than ever.

Where and How the Cast Filmed Season 18

Behind the scenes, production looked a little different this time. Season 18 was filmed in Los Angeles, including work on the Fox lot, while the series continues to use Philadelphia locations and imagery to build its Philly setting. Reports from production also showed Rob McElhenney and Kaitlin Olson filming scenes in Los Angeles back in June 2026.

Juggling schedules has clearly become part of the show’s reality at this stage of its run. Rob Mac has been busy with ‘Welcome to Wrexham’ and his real life commitments running a soccer club with Ryan Reynolds, Kaitlin Olson has been starring on ‘High Potential,’ and Danny DeVito remains in demand on the big screen with projects like ‘Jumanji Open World,’ leaving Charlie Day as the only cast member with writing credits this season.

Even with everyone’s schedules pulling in different directions, the results have resonated with critics so far. The season debuted to a 100 percent approval rating on Rotten Tomatoes. ScreenRant’s Grant Hermanns noted that although the season may not sing quite as well as its immediate predecessors, it still stands above many comedies currently on the air.

With the McPoyles crashing a Renaissance Faire, Guillermo del Toro popping up out of nowhere, and Sam’s wedding to Frank ending in tragedy, which returning face or new cameo caught you most off guard this season?