Chris Orr praises the "novel model of comedy" in The Hangover II:
[T]he comedy is not just black but noir–which is apt, given the formula to which [director/producer Todd] Phillips has adhered so rigidly. The missing person, the seamy urban setting, the gradual accretion of clues: The Hangover films are, essentially, hard-boiled crime stories spun into comic depravity, heirs as surely to Hammett, Chandler, and Cain as they are to Apatow and the Farellys. This was central to the appeal of the first movie. Even as it found room for scenes with taser-happy schoolkids and Mike Tyson singing "In the Air Tonight," there was an uncommon meticulousness to its structure: It succeeded not only as comedy but, in its way, as mystery.
The Dish 