Le Doulos (French pronunciation: [lə dulos]) is a 1962 French crime film written and directed by Jean-Pierre Melville, adapted from the novel of the same name by Pierre Lesou. It was released theatrically as The Finger Man in the English-speaking world, but all video and DVD releases have used the French title. Intertitles at the beginning of the film explain that the French title refers both to a kind of hat and to the slang term for a police informant.

Maurice Faugel, just released from prison after serving a six-year sentence, meets a friend, Gilbert, who is appraising the value of jewels from a recent heist. Maurice is planning a robbery the next day with two accomplices, Silien and Rémy. Maurice kills Gilbert with Gilbert's own gun and steals the jewels as well as a large sum of money.

It is later revealed that Gilbert killed Maurice's girlfriend Arlette to keep her from acting as an informant to the police when Maurice was sent to prison six years prior. Maurice leaves the house just as Nuttheccio and Armand, prominent gangsters, arrive to collect the loot. Maurice buries the jewels, money, and gun next to a lamppost. Maurice spends the evening at his girlfriend Thérèse's apartment. Silien arrives the next day with Maurice's friend Jean to deliver equipment for the robbery that evening. After Silien leaves, he uses a payphone to call Inspector Salignari.

That evening, Maurice and Rémy leave to rob a home in affluent Neuilly. Meanwhile, Silien comes to Thérèse's apartment, then beats her and ties her to a wall radiator, demanding to know the address of the robbery. The police arrive at the robbery. Inspector Salignari corners Maurice and Rémy, fatally shooting Rémy. Maurice and Salignari shoot it out; Maurice is hit in the shoulder, but Salignari is killed. Maurice leaves the gun next to Rémy's hand and runs away. He passes out just before a car pulls up.

Maurice wakes up in Jean's apartment, but neither Maurice nor Jean's wife Anita know who brought him there. Maurice resolves to find Silien, who he believes informed the police about the time and place of the robbery. He leaves Anita with a diagram showing where he buried the jewels, money, and gun, telling her to give it to Jean if something happens to him.

Because the police believe that Silien called Salignari, they assume he has information on the botched robbery. They question him, hoping to get the name of Rémy's accomplice, but Silien tells them he wasn't the informant. He mentions that he hopes to get out of the criminal underworld and live in a house he has built in Ponthierry. It is revealed that the car that rescued Maurice has been found wrecked, with Thérèse's body inside.

The police also suspect that Maurice killed Gilbert. They threaten to falsely implicate Silien in a drug case unless he helps them find Maurice. Silien complies and Maurice is found. Maurice claims that Gilbert was killed while Maurice was in another room of the house. The police offer to let him go if he has information on the robbery in Neuilly, but Maurice claims he has no information. He is jailed, where he meets a prisoner named Kern.

Silien finds the buried jewels, money, and gun beneath the lamppost. He visits Nuttheccio's club and speaks to Fabienne, a former girlfriend. He offers to get her out of her relationship with Nuttheccio if she will testify that Nuttheccio and Armand killed Gilbert. She eventually agrees. Silien kills Nuttheccio and plants the jewels in his safe, while Fabienne calls Armand to tell him Nuttheccio has found the stolen jewels and wants to see him. When Armand arrives, Silien kills him too, staging the scene to make it look like they killed one another.