
Acting
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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PaleyLive: It’s Always Sunny in Philadelphia 20th Anniversary Celebration!
as Self

BlackBerry
as Jim

Fool's Paradise
as Business Manager

The Thief Collector
as Jerry Alter

How It Ends
as John

The Hunt
as Richard

Archenemy
as The Manager

Mr. Bungle: The Night They Came Home
as Audience

Officer Downe
as Dominic

When Pigs Fly
as Uncle Al

Sirens
as Ethan Corbin II · 5 ep.

Hot Ones Versus
as Self · 1 ep.

Velma
as Fred (voice) · 21 ep.

Welcome to Wrexham
as Self · 1 ep.

Abbott Elementary
as Dennis · 1 ep.

Snacked
as Self · 1 ep.

The Fugitive
as Jerry Conwell · 5 ep.

The Kelly Clarkson Show
as Self · 2 ep.

Under A Rock with Tig Notaro
as Self - Guest · 1 ep.

A.P. Bio
as Jack Griffin · 42 ep.
Crank
2006