It’s Always Sunny in Philadelphia has maintained its status as one of the funniest shows on TV for two reasons… the characters are awful to the world and to each other in a way that makes Seinfeld look like a family sewing circle, and they know how to get really damn weird. Assisting them in this venture have been a cadre of notable characters like The Waitress, Cricket, and the McPoyles, but let’s not forget the one-off performances by familiar faces like Wade Boggs and many others that, in many cases, exposed themselves to the Always Sunny process for the sheer thrill of being a part of the show.
Christopher Lloyd
He’s hiding behind a white Santa beard in the Always Sunny Christmas Special from Season 9, but that’s absolutely Christopher Lloyd in flashback visiting Charlie’s house on Christmas to give some cheer to Charlie’s mom, who was apparently a yuletide prostitute. Pushed aside for years, thanks to young Charlie’s penchant for glue sniffing, he reacts somewhat violently by gnawing out the throat of a mall Santa Claus when the memories return.
Pablo Schreiber
Pornstache! Before Orange Is the New Black, Schreiber popped up all over television with roles on Weeds, Lights Out, and a brief cameo on It’s Always Sunny, where he played a man who had been wronged on Christmas when Mac unwittingly stole his toy robot.
Morena Baccarin
Brittany Daniel has appeared as Carmen — Mac’s transgender ex — a handful of times, but the character was actually played by Firefly and Homeland alum Morena Baccarin in the un-aired DIY pilot episode of It’s Always Sunny as a favor to her college friend, Glenn Howerton (Dennis).
Chase Utley
Philadelphia Phillies second baseman Chase Utley made an appearance on It’s Always Sunny in 2009 (along with teammate Ryan Howard), but the payoff, filmed for MLBFanCave five years later, is the real home run as Utley responds to Mac’s letter with one of his own.
Sinbad and Rob Thomas
https://www.youtube.com/watch?v=E9QOulJVZsc
Dennis’ erotic life takes a wrong turn, and he winds up in a rehab facility. But he’s not crazy. He’s just a little unwell and also scared sh*tless that Sinbad and Matchbox 20’s Rob Thomas will hurt him. But are they even there? Sadly, my letter writing campaign to get a New Adventures of Sinbad and Matchbox 20’s Rob Thomas didn’t take off. But, to be fair, it’s only been about five years, so a response could be coming any day.
Dax Shepard
Mac and Charlie joined a cult this season, and Dax Shepard got in on the action. The end result was the above image. I don’t think I need to say anything more.
Josh Groban
https://vimeo.com/76590915
Michael Bolton’s not the only crooner with a sense of humor. Despite his comedic timing, you can’t blame Dee for dumping his ass for Brad Pitt within her daydream, can you?
Sean “Puff Daddy/P-Diddy” Combs
https://www.youtube.com/watch?v=ROh_J8A-3NM
Sean Combs played Dr. Jinx, a yellow-jumpsuit clad “Doctor” who worked out of a garage and was supposed to help Charlie’s mom beat back cancer. It’s not on-par with Diddy’s comedic work in Get Him to the Greek or his “Come With Me” Godzilla music video, but it’s pretty great for a one-off cameo.
Chad L. Coleman
https://www.youtube.com/watch?v=lag1bXylX00
This is not a hallucination brought on by a zombie bite. That’s Tyreese from The Walking Dead recounting the sad saga of his worn out jean shorts to a random partygoer. Coleman popped up in three episodes of It’s Always Sunny. Even though he was Cutty on The Wire and the voice of Coach in the Left 4 Dead game, this might be his best work, and that’s no slight.
Tom Sizemore
https://www.youtube.com/watch?v=XZGiczmT_0c
Sizemore appeared in the same episode as Chase Utley and Ryan Howard, but his storyline was more than a bit different. He played a Jersey-bound trucker on the hunt for some street-side strange who mistakes Charlie and Dennis for a pair of male hookers (happens) and tries to take them to a hotel before they ditch him. Which is a bit rude, if you ask me.
