One Take Only(2001)

Hapless hustler Bank, rescues a miserable young prostitute, Som, from street thugs, and the two begin a quiet romance. When Bank has the opportunity to become a drug-runner for an affluent dealer, he resolves to raise enough money to rescue Som from the sex trade. But, as Bank descends deeper into Bangkok's violent criminal underworld, the possibility of leaving his old life behind grows ever more distant.

Official site