Claim: The Hangover Part III stars Zach Galifianakis.

The Hangover Part II is a 2011 American comedy film produced by Legendary Pictures and distributed by Warner Bros. . Pictures . It is the sequel to the 2009 film The Hangover and the second installment in The Hangover trilogy . Directed by Todd Phillips , who co-wrote the script with Craig Mazin and Scot Armstrong , the film stars Bradley Cooper , Ed Helms , Zach Galifianakis , Ken Jeong , Jeffrey Tambor , Justin Bartha , and Paul Giamatti . It tells the story of Phil , Stu , Alan , and Doug as they travel to Thailand for Stu 's wedding . After the bachelor party in Las Vegas , Stu takes no chances and opts for a safe , subdued pre-wedding brunch . Things do not go as planned , resulting in another bad hangover with no memories of the previous night .   Development began in April 2009 , two months before The Hangover was released . The principal actors were cast in March 2010 to reprise their roles from the first film . Production began in October 2010 , in Ontario , California , before moving on location in Thailand . The film was released on May 26 , 2011 and became the highest-grossing R-rated comedy during its theatrical run .   A third and final installment , The Hangover Part III , was released on May 23 , 2013 .