Louis Székely, better known as Louis C.K., is an American comedian, actor, writer, producer, director, and editor. He voiced The Horrifying Sweaty One-Armed Monstrosity in the Gravity Falls episodes "Weirdmageddon Part 1," and "Weirdmageddon 3: Take Back The Falls."
Louis Székely was born in September 12, 1967 in Washington, D.C. He is an American comedian, actor, writer, producer, a director, and a editor. C.K. moved to Mexico City as an infant and learned Spanish as his first language, learning English once he moved back to the U.S. at age 7.
He began his career writing for several comedy shows in the 1990s and early 2000s for comedians including David Letterman, Conan O'Brien, and Chris Rock. Also in this period, he was directing surreal short films and went on to direct two features — Tomorrow Night (1998) and Pootie Tang (2001) — before he starred in the short-lived HBO television sitcom Lucky Louie in 2006.
Louie, an acclaimed semi-autobiographical comedy-drama series that C.K. created, stars in, writes, directs, executive produces, and is the primary editor of, began airing in 2010 on FX. He had supporting acting roles in the films The Invention of Lying (2009), American Hustle, and Blue Jasmine (both 2013).
- Louis C.K., while voicing The Horrifying Sweaty One-Armed Monstrosity, improvised most of his role during the end credit scene of "Weirdmageddon Part 1" where he says, "I gotta call my mother." In fact, there are nearly 30 minutes of him improvising different ways the monstrosity could beg someone to get into his mouth.
- After 5 sexual assault accusations, his character was re-dubbed by Alex Hirsch for all future airings as of December 19th, 2017.