Dan Harmon's meta masterpiece Community ran from 2009 to 2015 and it revolved around the lives of six random students at Greendale Community College. The main cast members include Alison Brie, Joel McHale, Donald Glover, Gillian Jacobs, Dani Pudi, and Chevy Chase. As is the norm in sitcoms, many Community episodes welcomed celebrity guests.
Guest characters typically got cast for small roles and compared to celebrity guests on other TV shows, barely had any lines at all. Consequently, it's hard to remember everybody on the long list of celebs who were featured in the show's six seasons.
10 Tony Hale
Fans of Arrested Development might know Tony Hale for his portrayal of Buster, the youngest and most helpless of the Bluth bunch.
In season 2's 'Beginner Pottery', Hale played Professor Holly, the sculpting professor who abhorred "ghosting": reenacting the famous scene from the romantic drama Ghost, starring Patrick Swayze and Demi Moore.
9 Betty White
In 'Anthropology 101', Betty White stepped in as Professor June Baurer. Since she ended up choking Jeff, she was given a paid leave of absence and so, John Oliver's character stepped in to take over the class. Since he thought everything could be seen through a lense of studying humanity, they just watched funny YouTube videos.
Betty White is most known for her time on Golden Girls. The fact that she agreed to be a guest star on Dan Harmon's show proves that she truly has a great sense of humor.
8 Matt Jones
Matt Jones made really small appearances on Community in season 1, a year after he got a more prominent role on Breaking Bad as Badger.
In the third episode of season 1, he brought the group some coffee and if some fans of Breaking Bad didn't recognize him rightaway, they surely did when he opened his mouth and started talking.
7 Adam DeVine
In season 4's 'Cooperative Escapism in Familial Relations', Adam DeVine played Jeff's younger half-brother, William Winger Jr. It was an intense episode that offered insight into Jeff's family history. He finally confronted his father who abandoned him when he was seven.
Adam DeVine's most famous roles include Andy from Modern Family, Adam DeMamp on Workaholics, and Bumper in Pitch Perfect.
6 Josh Holloway
Josh Holloway is not exactly a household name. Fans of ABC's drama Lost know him as Sawyer, a troubled, good-looking conman. Holloway appeared on season 2's paintball finale, 'A Fistful of Paintballs' and portrayed a stranger, called Black Rider.
Community owes some of its success to its self-referential humor. Abed references Holloway's role as Sawyer on Lost by saying that Black Rider is "handsome enough for network television".
5 Hillary Duff
In the early 2000s, Hillary Duff typically played likable underdogs, but in Community, she portrayed a mean girl, Meghan She made Annie, Britta, and Shirley change seats in 'Aerodynamics of Gender' and the trio took revenge when they realized that Abed is great at reading people's flaws and throwing them in their face.
Abed essentially turned into a bully and the only way to restore peace was to tell Meghan how to insult him so he would look defeated and things could go back to normal.
4 John Goodman
Season 2 opened up with 'Anthropology 101' and Betty White, but season 3 opened up with 'Biology 101' and John Goodman. He portrayed Vice Dean Robert Laybourne, but he wasn't the only guest star of the episode: Michael K. Wiliams portrayed the biology teacher, Professor Kane.
John Goodman is mostly known for his roles on Roseanne and several movies by the Coen brothers.
3 Brie Larson
The Captain Marvel star first appeared on Community in season 4's 'Herstory of Dance' where she portrayed Rachel, Abed's romantic interest. He was set on two dates in the episode, but he realized he liked Rachel, the coatcheck girl, the best.
The fourth season of Community is considered the show's worst. NBC fired the creator Dan Harmon and the show simply wasn't what it's supposed to be without him. Brie Larson's character made a return in season 5.
2 Owen Wilson
'Investigative Journalism' is definitely one of the best episodes of season 1. Not only did it feature Jack Black as Buddy, a "chubby agile guy", who tried his hardest to get accepted to the study group; in the very last seconds of the episode, Owen Wilson appeared as a leader of the 'cool group'.
The episode just kept getting more and more hilarious. Too bad Wilson only had one line. He would've made a great addition to the cast.
1 Martin Starr
Martin Starr, the star of Silicon Valley and Freaks and Geeks, was Greendale's political science teacher, Professor Cligoris. In season 3's 'Geography of Global Conflict', Annie butted heads with another Annie, a girl who shared her personality and ambition.
Not only did this new Annie manage to win over Cligoris, she also stole Annie's UN model. What's more, Annie and Jeff realized they have mutual feelings towards one another. But as this is Community and not How I Met Your Mother, nothing happened between them at that point.