Bradley Cooper was quite busy in the four years in between "Wedding Crashers" and "The Hangover," but none of his gigs were especially noteworthy. His most memorable roles during this time were as the lead character in the short-lived sitcom "Kitchen Confidential" (based upon the life of Anthony Bourdain), a six-episode arc on the bananas Ryan Murphy show "Nip/Tuck," and a turn as a cheating husband in the ensemble rom-com "He's Just Not That Into You." In 2009, "The Hangover" became a massive hit –- earning nearly $470 million worldwide (via Box Office Mojo) and catapulting Cooper to leading man territory.

"The Hangover" focuses on a group of friends who travel to Las Vegas for a bachelor party, have a crazy, raucous night during which they lose the groom, and then retrace their steps the next day. Cooper plays Phil Wenneck, a married schoolteacher and leader of the "Wolf Pack," who is both charming and a complete douchebag all at once. Unlike its two sequels, the original "Hangover" film was well-received by critics, many of whom commented upon Cooper's portrayal favorably. Writing for Rolling Stone, legendary critic Peter Travers said, "Cooper, from 'Wedding Crashers,' can spoof his leading-man looks like a born goofball" and A.O. Scott of The New York Times said, "It is Mr. Cooper who offers the most interesting variation on an old standard, playing his aggressive, cocky frat boy with a snarl of rage that masks an anxiety as hard to account for as it is to miss."