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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The Strangers
As Mike
Fool's Paradise
As Business Manager
Crank: High Voltage
As Doctor
Serenity
As Lilac Young Tough
Everything Must Go
As Gary
A Very Sunny Christmas
As Dennis Reynolds
The Thief Collector
As Jerry Alter
Coffee Town
As Will
Crank
As Doctor
BlackBerry
As Jim Balsillie
Must Love Dogs
As Michael
The Nightman Cometh: Live
As Dennis Reynolds
A Tribute to Ryan Dunn
As Self
Officer Downe
As Dominic
When Pigs Fly
As Uncle Al
Two Weeks
As Matthew Bergman
Monday Night Mayhem
As Dick Ebersol
The Hunt
As Richard
Archenemy
As The Manager
Mr. Bungle: The Night They Came Home
As Audience
How It Ends
As John
EDNY
As Paul Webster
The Job
As Young Guy
The View
As Self
It's Always Sunny in Philadelphia
As Dennis Reynolds
That '80s Show
As Corey Howard
ER
As Nick Cooper
Vietnam in HD
As Don Devore
Glenn Martin, DDS
The Cleveland Show
American Dad!
As Animal Control Guy #1 (voice)
The Mindy Project
As Cliff Gilbert
A.P. Bio
As Jack Griffin
Welcome to Wrexham
As Self
Jimmy Kimmel Live!
As Self
The Kelly Clarkson Show
As Self
Velma
As Fred (voice)
Snacked
As Self
Unsupervised
As Clint (voice)
Under A Rock with Tig Notaro
As Self - Guest
Late Night with Seth Meyers
As Self
Fargo
As Don Chumph
Family Guy
As (voice)
Sirens
As Ethan Corbin II
The Fugitive
As Jerry Conwell
Conan
As Self