The film revolves around a group of high school and university students during their school break, and the relationships that develop (or don't). Four romantic threads are interwoven in the film's plot. Both Pu (Charlie Trairat) and Mai (Sirachuch Chienthaworn) are in competition for Nana (Ungsumalynn Sirapatsakmetha) while class geek Jo (Ratchu Surachalas) is in love with a popular girl C (Chutima Teepanat). Meanwhile Oh Lek (Focus Jirakul) is wild about Taiwanese pop sensation Didi (Lu Ting Wei), and Hern (Chantawit Thanasewee) is thinking of cheating on his girlfriend Nuan (Thaniya Ummaritchoti) when he meets Japanese tourist Aoi (Sora Aoi).

One dark night, a former native of a rural Thai village, has his men steal the head of the town's Ong Bak (Buddha statue) to win ruthless crime boss Khom Tuan. The locals regard the theft as a catostrophe, and seek a champion to retrieve their lost treasure. They find their man in Ting (Tony Joo) an orphaned youngster raised at the local temple, and schooled by Pra Kru, a kindly monk, in an ancient system of Muay Thai, Nine Body Weapons. Ting travels to the mean streets of Bangkok, where he's forced to compete in illegal street fights, taking on both and foreign opponents to win the head of ONG BAK from the ruthless crime boss.