When three friends finally come to after a raucous night of bachelor-party revelry, they find a baby in the closet and a tiger in the bathroom. But they can't seem to locate their best friend, Doug – who's supposed to be tying the knot. Launching a frantic search for Doug, the trio perseveres through a nasty hangover to try to make it to the church on time.

The Hangover crew heads to Thailand for Stu's wedding. After the disaster of a bachelor party in Las Vegas last year, Stu is playing it safe with a mellow pre-wedding brunch. However, nothing goes as planned and Bangkok is the perfect setting for another adventure with the rowdy group.