It's been two years. Phil (Bradley Cooper), Stu (Ed Helms) and Doug (Justin Bartha) are happily living uneventful lives at home. Tattoos have been lasered off, files purged. The last they heard from disaster-magnet Leslie Chow (Ken Jeong), he'd been tossed into a Thai prison and, with him out of the way, the guys have very nearly recovered from their nights prowling the seamy side of Las Vegas in a roofie'd haze, and being kidnapped, shot at, and chased by drug-dealing mobsters in Bangkok.
The only member of the Wolfpack who's not content is Alan (Zach Galifianakis). Still lacking a sense of purpose, the group's black sheep has ditched his meds and given in to his natural impulses in a big way—which, for Alan, means no boundaries, no filters and no judgment—until a personal crisis forces him to finally seek the help he needs.
And who better than his three best friends to make sure he takes the first step.
This time, there's no bachelor party. No wedding. What could possibly go wrong? But when the Wolfpack hits the road, all bets are off.