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.

Continuing from Ong Bak 2's 1440s, Prince Tien fails to revenge his parents' murder by the evil new ruler. The beaten Tien is rescued. Can he bring peace to the kingdom?