Seven-foot, gentle Giant Barney Emerald is drugged and robbed while on holiday in Pattaya. He befriends two Thai sisters, one who can speak English and another who is a Muay Thai kick-boxing champion. He stays with them until he can recover his passport. After eating some spicy “somtum” at their mother’s restaurant, he accidentally demolishes the place. They discover that when Barney eats the spicy somtum, he has a physical reaction that sends him into a raging and violent martial-arts frenzy. The girls use the somtum to control Barney’s powerful reactions in order to earn back his stolen money and take down some local crime lords.