Tony "le Stéphanois" has done five years for a jewel heist, and is now out on the street and down on his luck. His friend Jo approaches Tony about another jewel heist in which they and Mario would stealthily cut the glass on a Parisian jeweler's front window and grab some gems. Tony opts not to participate. Tony learns that his old girlfriend, Mado, has now aligned herself with Pierre Grutter. Finding Mado at Grutter's nightclub, he invites her back to his rundown flat. Mado has been well-kept, and Tony savagely beats her for being so deeply involved with Grutter. Tony changes his mind about the heist; he now accepts on the condition that they hit the jeweler's safe, not the window. Mario, an Italian, suggests they employ the services of his compatriot César, a safe cracker. The four team up and plan a way to work around the ingenious alarm system guarding the jewelry shop.Casing the store, the group decides to drill through the ceiling from an upstairs flat which will be vacant on a Sunday night extending into Monday morning before the jeweler returns. The suspenseful break-in completed, the criminals seem to have triumphed. Without the others' knowledge, César has pocketed a diamond ring as a gift for his mistress Viviane, a chanteuse at Grutter's club. The four men arrange to fence the loot with a London contact. Meanwhile, Grutter has seen Mado and her injuries; Mado breaks off their relationship. From this, Grutter infers that Tony is at the root of Mado's decision; he then gives drugs to his heroin-addicted brother and tells him to murder Tony. Grutter sees the diamond Cesar gave to Viviane and realizes that César and Tony were responsible for the jewel theft. Grutter forces César to confess. Seeking revenge and money, Grutter's gang brutally murders Mario and his wife Ida. Tony retrieves Mario's share of the jewels and pays for a splendid funeral for him. Tony goes looking for Grutter and finds the captive César, who confesses to ratting him out to Grutter. With regret, Tony kills César.Meanwhile, Grutter's thugs have kidnapped Jo's five-year-old son Tonio, demanding that Tony give over the loot or young Tonio will be killed. The London fence arrives with the cash, which now seems pointless to Jo, who along with his wife, is tormented with worry for their son. Seeking the boy, Tony tracks him down at Grutter's country house and kills Grutter's brothers Rémi and Louis to save him. On the way back to Paris, Tony is told that Jo has cracked under the pressure and has taken the money to the house for Grutter. Grutter kills Jo, and then is killed by Tony, who is mortally wounded. Bleeding profusely, Tony drives maniacally back to Paris and delivers Tonio home safely. Tony dies in his car as police and bystanders close in on him and his remaining loot.
What does Csar steal for his girlfriend?
ring