Glenn Franklin Howerton III (born April 13, 1976) is an American actor of television and film. He is best-known for his role as Dennis Reynolds on FX's It's Always Sunny in Philadelphia (on which he is also a writer and executive producer). He also played Corey Howard on the short-lived 2002 sitcom That '80s Show.
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Glenn Franklin Howerton III (born April 13, 1976) is an American actor, writer, and producer. He is best known for playing Dennis Reynolds on the FX/FXX sitcom It's Always Sunny in Philadelphia (2005–present), which he co-developed and on which he serves as an executive producer and writer alongside the other main cast members.
Howerton's other notable performances include Cliff Gilbert on The Mindy Project (2012–2017), Don Chumph on the first season of Fargo (2014), Jack Griffin on A.P. Bio (2018–2021), and Jim Balsillie in the film BlackBerry (2023). He also co-hosted The Always Sunny Podcast (2021–2023) with his fellow Always Sunny co-stars and co-creators Rob Mac and Charlie Day.