After a series of disappointments, director Todd Phillips struck fort knox with this ensemble comedy concerning four friends and their misadventures during a pre-wedding trip to Las Vegas. Much of the film is presented in flashback, as Phil (Bradley Cooper), Stu (Ed Helms) and Alan (Zach Galifianakis) desperately try to remember the events of the previous evening in the hopes of uncovering the whereabouts of the groom Doug (Justin Bartha) before the wedding. Phillips covers similar ground to his previous hit Old School, but it's the wildcard addition of the unpredictable Galifianakis that brings some life to the mostly familiar material. There are flashes of brilliance, particularly in some amusing cameos and supporting roles, but it's generally forgettable. The creators hope that lightning will strike twice with their upcoming anxiously anticipated sequel.