God of Gamblers

Do san is a movie starring Chow Yun-Fat, Andy Lau, and Joey Wang. A master gambler loses his memory, and is befriended by a street hustler who discovers his supernatural gambling abilities.
Ko Chun, an extremely talented and well known gambler. On the eve of a big confrontation with a famous Singaporean gambler, Ko walks into a trap set by Knife, an avid but a so-so gambler, meant for an Indian neighbour. Struck on the head, Ko suffers from amnesia and regresses to a child-like state. Knife takes care of Ko and begins to exploit Ko's gambling talents.