City of Ghosts (2003)

Jimmy Cremming (Dillon) finds himself in Bangkok after fleeing the investigation of an insurance scam in the United States. He discovers his partner and mentor Marvin (Caan) has surfaced in Cambodia, and sets off to get his promised cut of the action. What he finds instead is a bizarre and ominous environment where cleverness is bait. The further Jimmy searches for Marvin, the deeper he plunges into torment.