From Monkey Island wiki
Patrick Hallahan is an actor who had made a short appearance in his first role in the 2003 film The Kiss as a "First Person with Umbrella". He has also made a few other appearances, including the AA Director in an episode of It's Always Sunny in Philadelphia, and Starscream in Transformers: Beginnings. He has done the role of the Bouncer, Sharptooth the Cannibal, and one of the Mystery Pirates in The Secret of Monkey Island: Special Edition; and Standard-Mode Chester, Crutch and Rich in Monkey Island 2 Special Edition: LeChuck's Revenge. Surprisingly, Hallahan has also done Phineas, a.k.a. Fin (one of the Men of Low Moral Fiber), in both Special Editions of these games.