Bangkok Revenge (2011)

Manit was only ten years old when they killed his parents. A brutal, thoughtless murder, which included putting a bullet in his own brain. They should have finished the job. Rescued from death by a master of Muay Thai boxing, and afflicted with ataraxia - a brain injury that removes all human emotion - Manit has spent his life training to be a killing machine. It's 20 years later, and he's coming for them all. With fists, feet, and bloody vengeance, he's going to make them wish they were dead already.