William Emerson Arnett (born May 4, 1970) is a Canadian actor, comedian, and producer. He is best known for his roles as Gob Bluth in the Fox/Netflix series Arrested Development (2003–2006, 2013, 2018–2019), receiving a nomination for Primetime Emmy Award for Outstanding Supporting Actor in a Comedy Series, and as BoJack Horseman in the Netflix series of the same name. He has appeared in films such as Let’s Go To Prison (2006), Blades Of Glory (2007), Semi-Pro (2008), G-Force (2009), Jonah Hex (2010), and Show Dogs (2018). His performance as Devon Banks in 30 Rock earned him four Primetime Emmy Award for Outstanding Guest Actor in a Comedy Series nominations.
His baritone voice has landed him voice acting jobs, including Ice Age: The Meltdown (2006), Ratatouille (2007), Horton Hears a Who! (2008), Monsters vs. Aliens (2009), Despicable Me (2010), The Nut Job (2014), Dolittle (2020), and as Batman in the Lego Movie franchise. He also served as an executive producer and voices the titular character of the Netflix series BoJack Horseman (2014–2020), for which he won an Annie Award at the 46th Annie Awards. His involvement with The LEGO Group continues as Fox Network announced him as the host of their show LEGO Masters, which premiered on February 5, 2020. Since July 2020, he has co-hosted the comedy podcast SmartLess.