- "Fucking punk-ass pieces of shit! What, d'you forget I'm a captain?!"
- ―Jimmy tries to threaten Christopher and Silvio[src]
James "Jimmy" Altieri, also known as Little Jimmy Altieri, portrayed by Joe Badalucco, is a recurring character in The Sopranos. A capo in the DiMeo crime family, Jimmy runs the Altieri Crew, and frequently engages in illicit acitvity.
Jimmy was made captain of the Altieri Crew at an unknown point in time, and he was seen in the back room of Satriale's on Christmas 1995, at the time Pussy became an FBI informant. Not much is known about Jimmy's past otherwise, although he also became an informant later on at some point.
- "All we want you to do is talk to him. After all, he's your uncle. Come on!"
- ―Jimmy asks Tony to reason with Junior[src]
The capos; Jimmy, Raymond, Larry and Tony, meet at the Bada-Bing to discuss Junior's behavior now that Jackie is on his deathbed. Jimmy, like Raymond and Larry, agree that Tony should step up as boss since he is the most capacitated for the position, believing that he would get New York's approval if he did. After Tony gives Junior the title of boss, Jimmy tells Tony he's worried about the money end at Jackie's funeral, although Tony reassures him that that's natural, and that it'll all be good, since they all agreed that they would let Junior be the lightning rod for the FBI to go after, when in reality all decisions are made by Tony, and he and the others would stay safe. Later, Sammy Grigio, the leader of a card game protected by Jimmy, gets beaten up by Mikey Palmice on Junior's orders, who "ain't respecting old arrangements". The capos meet again to sort that out and also because Junior ordered Rusty Irish's death, who was Larry's biggest earner. They protest to Tony that they aren't getting paid enough and that Junior's reasoning was completely unfair, citing Sammy's beating as an example. Jimmy suggests Tony talk to his uncle and try to reason with him, and after he does so, Junior starts paying everyone equally and matters are resolved. When everyone cheers for Junior as the new boss at a party later on, the FBI takes undercover pictures of family members, including Jimmy's.
At Larry's daughter's wedding, he tells his fellow mobsters that FBI indictments are on the way and that they should lay low. Jimmy is amazed when Christopher tells him they're gonna want him since he's "OC", disregarding his standing in the family. Jimmy tells his wife to go and they quickly get out of the wedding. When talking about how brilliant it was to hide his money and guns inside his mother's room at Green Grove, Larry and Tony are met by Jimmy, who is trying to get his own mother into Green Grove as well, but says they want to see his financial statement, and isn't sure they're gonna accept her. Jimmy later organizes a card game with Big Pussy and other associates. Suddenly, FBI agents break in, finding lots of concealed revolvers and shotguns. They seize Jimmy and Pussy runs away. An agent sarcastically asks Jimmy "do you know what this is?" while holding a revolver, to which Jimmy responds "It's a fucking gun!".
His friends are initially worried that he's still in jail, however the thought quickly escapes Tony's brain when he is informed by corrupt police officer Vin Makazian that Pussy Bonpensiero is an FBI informant. After much flip-flopping over whether or not he actually is, and Makazian killing himself over personal issues, Jimmy shows up uninvited at Tony's house after bailing out, and asks if they can talk in the basement. Jimmy starts asking questions to Tony about the Colombian drug money his men had seized one episode prior, and generally makes himself look suspicious. Although Jimmy may not know it, Tony picks up on this and ironically tells him he's a "lucky man" to make it out so fast. Jimmy casually gets out of his house with the excuse of enforcing his authority over his earners, meanwhile Tony drives all the way to Satriale's to tell his friends that Jimmy was the rat, assuming Makazian mistook Jimmy and Pussy's similar-looking appearance ("two fat fucks with black hair", as he puts it). Jimmy then attends Mariolina Capuano's funeral, where he kicks up to Junior, telling him he did good on killing Brendan Filone. Christopher tells Tony that when Jimmy's at the joint now they only feed him "deliberate bullshit", so that he can't report anything relevant to the FBI. Tony asks him not to do anything with him for now.
Ultimately, however, Tony decides to go with his instinct, and after a sitdown, Tony convinces Junior and gets his blessing to get rid of him. Christopher lures Jimmy to a hotel room in New York, making him think they're only there to spend time with some Russian prostitutes, who he says are Tony's mistress Irina's friends. After getting into a room, Christopher asks him to sit down, then suddenly, Silvio enters the room through a door behind Jimmy, who tries to reach for a gun inside his shoe, but is quickly disarmed by Chris. Silvio then puts his pistol against the back of Jimmy's skull. When Jimmy nervously tries to intimidate them by stating that he's a captain, Silvio mocks him "Why don't you call for help in your radio mic, you fucking rat?". Jimmy breathes heavily "Oh God…!", before Silvio shoots him, splattering his brains all over the room. Silvio asks Christopher to "get the piano dolly." so as to move Jimmy's body. He is found in an alleyway with a rat stuffed in his mouth, indicating he was a traitor and worked for the FBI. Christopher even goes so far as to phone in a bomb scare to Jimmy's wake, but Silvio tells him that's "over the top".
Tony is trying to pin down exactly when Pussy became an informant, which is shown throughout flashback sequences. In one flashback, set in Christmas 1995, Jimmy can be seen in the background entering the backroom of Satriale's, where he is appalled when seeing Pussy and his friends fighting over seemingly nothing. He then exits through the door.
The rat being stuffed into Jimmy's mouth after his demise is a mafia message job which indicates that he was a traitorous rat (or in this case, an FBI informant).