Bangkok Revenge (movie, 2011)

Manit (Jon Foo) witnessed the murder of his parents when he was just 10 years old. The killers shot him in the head, but he miraculously survived. However, the damage to his brain left him unable to experience regular human emotions. A martial arts master saved him and took him in. Twenty years later, Manit has become a master of martial arts himself. He returns to the scene of the crime, seeking justice.