Kung-Fu Sting (1976)

The grandson of a petroleum company president is kidnapped in Rome. The kidnappers want $10 million dollars in ransom money. The boy's grandfather wants his grandson back but doesn't want to pay, so he hires detectives to go after the boy. Three local detectives have a go at it, and fail with comedic humiliation. While lamenting their frustrations at a Chinese restaurant, they notice two young waiters playfully exchanging martial arts moves and instantly enlist the eldest to get the boy back before the kidnappers cut off his ear.