Lucas and Moore wrote the script after executive producer Chris Bender's friend disappeared and had a large bill after being sent to a strip club. After Lucas and Moore sold it to the studio for $2 million, Philips and Jeremy Garelick rewrote the script to include a tiger as well as a subplot involving a baby and a police cruiser, and also including boxer Mike Tyson. Filming took place in Nevada for 15 days, and during filming, the three main actors (Cooper, Helms and Galifianakis) formed a friendship.
The Hangover was released on June 5, 2009, becoming a critical and commercial success. It became the tenth-highest-grossing film of 2009, with a worldwide gross of over US$467 million. Critics praised the film's comedic approach but criticized it for its vulgarity. The film won the Golden Globe Award for Best Motion Picture – Musical or Comedy, and received multiple other accolades. It is the tenth-highest-grossing film of 2009 in the world, as well as the second highest-grossing R-rated comedy ever in the United States, surpassing a record previously held by Beverly Hills Cop for almost 25 years and later being surpassed by Ted in 2012. Out of all R-rated films, it is the third highest-grossing ever in the U.S., behind only The Passion of the Christ and The Matrix Reloaded. A sequel, The Hangover Part II, was released in 2011, and a third and final film, The Hangover Part III, is set for release in 2013.
Plot
Celebrating his coming marriage to Tracy Garner, Doug Billings and his friends Phil Wenneck, Stu Price, and Tracy's brother Alan travel to Las Vegas for a bachelor party, staying at Caesars Palace.
The next morning, Phil, Stu and Alan awaken to find they have no memory of the previous night and Doug is nowhere to be found. Stu is missing a tooth, their hotel suite is in disarray, a tiger is in their bathroom, and a baby is in the closet. They find Doug's mattress impaled on a statue outside of their hotel and when they ask for their Mercedes, the valet delivers a police cruiser.
Following clues to their steps, the trio travel to a hospital where they discover they were drugged with rohypnol, causing their memory loss, and that they came to the hospital from a chapel. At the chapel they learn that Stu married a stripper, Jade, despite having a long-term relationship with his mean-spirited girlfriend, Melissa. Outside the chapel, the trio are attacked by gangsters saying they are looking for someone. They flee and visit Jade, discovering that she is the mother of the baby, before being arrested by the police.
Having been told that the Mercedes has been impounded, the trio is released when they volunteer to be targets for a taser demonstration. While driving the Mercedes, they discover a naked man in the trunk who attacks them and flees. Alan confesses that he drugged their drinks to ensure they had a good night, thinking the drug to be ecstasy.
Returning to their villa, they find Mike Tyson, who orders the trio to return the tiger to his mansion immediately. Stu drugs the tiger with the remaining rohypnol and they drive towards Tyson's home in the Mercedes, but the tiger attacks them and damages the car's interior. After pushing the car the rest of the way to avoid the tiger, Tyson shows the trio footage of them stealing the tiger to help them locate Doug. While driving, their car is struck by another vehicle intentionally; the passengers are revealed to be the gangsters from the chapel and their boss, Leslie Chow – the naked man from their trunk – who accuses the trio of stealing $80,000 of his money and kidnapping him. Chow says he has their friend, and threatens to kill him if his money is not returned. Unaware of the location of Chow's $80,000, Alan, with help from Stu and Jade, uses his knowledge of card counting to win $82,400 playing Blackjack. They meet with Chow and exchange the money, only to find that "Doug" is the drug dealer who inadvertently sold Alan the roofies.
With the wedding occurring in hours, Phil tells Tracy they cannot find Doug. Following a conversation with "Black Doug", Stu realizes where Doug is. The trio travel back to their hotel where they find Doug on the roof, moved there on his mattress while he was asleep, as a practical joke by Stu, Phil and Alan. Before leaving, Stu makes arrangements to go on a date with Jade the following week. With less than four hours before the wedding and with no flights available, the foursome race home, with Doug revealing he has possession of Chow's original $80,000. Despite their late arrival, Doug and Tracy are married and Stu breaks up with Melissa after having grown tired of her controlling his life. As the reception ends, Alan finds Stu's digital camera detailing the events they cannot remember and the four agree to look at the pictures together before deleting the evidence of their exploits.
