When the head of Ong-Bak, the sacred Buddha of a poor village is stolen, the population is plunged into misery. The Buddha was the focal point of an anniversary vigil believed to bring rain to the drought-stricken area. Young Ting is selected by the villagers to travel to Bangkok and rescue the relic in time for their ceremony. Ting has an affinity with the statue as he was left on the temple steps as a baby and raised by monks, who taught him muay thai, but forbade him to use it in combat. But now he is forced to delve into a seedy underworld and try to avoid temptation...