The Hangover Part III

Two years after the events in Bangkok, Leslie Chow escapes confinement during a prison riot. Meanwhile, Alan Garner causes a multi-car freeway pileup after he purchases a giraffe and accidentally decapitates it on a low overpass. Alan's father Sid, angry about the incident and furious that Alan won't take responsibility for his actions, dies of a heart attack. At the funeral, Alan's brother-in-law Doug Billings informs Phil Wenneck and Stu Price that Alan has been off his ADHD medication and is out of control. The group attends an intervention in which Alan agrees to visit a rehabilitation facility in Arizona where he can seek treatment, as long as his friends, the "Wolfpack", take him there.