La tricheuse (1960)

Lily is a lost girl who lived a miserable childhood. Now she works for Martial, a small-time crook. One day, she meets Armand, a shy high school student, the son of a renowned surgeon. And she discovers true love. But Martial is nothing of a tender heart, on the contrary. He manipulates Lily into forcing Armand to mimic the signature of his father, which will allow his gang to obtain drugs with a view to selling them.