Zachary Knight "Zach" Galifianakis (pronounced "Galli-fin-ack-iss) is an American stand-up comedian, actor, and pianist, who is best known for his role as Alan Garner in The Hangover film trilogy. He is also well-known for his roles in other films, such as Ethan Tremblay/Ethan Chase in Due Date, Humpty Dumpty in DreamWorks' Puss in Boots, Marty Huggins in The Campaign, Jake in Birdman, David Scott Ghantt in Masterminds, and the Joker in The Lego Batman Movie.
For Disney, he played Ben Kendall in G-Force and Hobo Joe in The Muppets and Muppets Most Wanted, and the Happy Medium in A Wrinkle in Time. He also portrayed the Bus Stop Man in the 2001 Touchstone Pictures film, Bubble Boy, Dexter in Corky Romano, and Luke in Out Cold. He will voice the title character in Ron's Gone Wrong.