Kaitlin Olson was a part of the theater troupe the Groundlings.
She began her career in the Groundlings , an improvisational group in Los Angeles , California , and had minor roles in several television series before being cast as Deandra `` Sweet Dee '' Reynolds on the FX black comedy series It 's Always Sunny in Philadelphia in 2005 .	Groundlings	Groundlings	FX	FX Network	black comedy	black comedy
The Groundlings are an improvisational and sketch comedy troupe and school based in Los Angeles , California .	improvisational	Improvisational theatre	sketch comedy	sketch comedy	Los Angeles	Los Angeles	California	California
