Charles Peckham Day is an American actor, screenwriter, producer, and comedian. He is best known for playing Charlie Kelly on the sitcom It's Always Sunny in Philadelphia (2005–present), for which he was nominated for a Critics' Choice Television Award and a Satellite Award in 2011. In 2020, he co-created the Apple TV+ comedy series Mythic Quest alongside Rob McElhenney and Megan Ganz. In film, he is known for his role as Dale in the films Horrible Bosses (2011) and its 2014 sequel, as well as for his roles in Monsters University (2013), Pacific Rim (2013), The Lego Movie (2014), Fist Fight (2017), Pacific Rim: Uprising (2018), and The Lego Movie 2: The Second Part (2019). From 2018 to 2019, Day was the executive producer on the Fox comedy The Cool Kids.