- "My mistake. Carlo's lipstick was on Vito's cock!"
- ―Fat Dom making a joke about Vito Spatafore's sexuality[src]
Fat Dom, as his nickname implies, is an overweight member of the Lupertazzi crime family, and he eventually became a soldier in the Leotardo Crew. He had a daughter at one point who went on to live in Metuchen.
When Johnny Sack pleads guilty in federal court, Fat Dom, along with Phil and other family members, are watching the news at their social club. Fat Dom, like Phil, is indignant at John's testimony, saying he "should have stood trial like a man". Later, Vito Spatafore returns to New Jersey following his stay in New Hampshire after it was revealed he was gay, with Phil being one of the most aggrieved at his homosexuality. He becomes especially angry after he finds out that Tony won't do anything about him (not knowing that he had actually already ordered his death to satisfy Phil's desires), so he decides to take matters into his own hands. As Vito is coming to spend the night at his motel room in Fort Lee, Fat Dom and Gerry Torciano ambush him while the lights are out and beat him to the ground. Fat Dom duct tapes his mouth as Gerry holds him down, and when he turns on the lights, Phil literally comes out of the closet. He sits on the bed and angrily tells Vito he is a "fucking disgrace", before Fat Dom and Gerry beat him to death.
Fat Dom later goes over to Satriale's, where Silvio and Carlo are at, to give Silvio an envelope of money from a game in Canarsie. Silvio offers to let him stay, but Fat Dom says he needs to stop by his daughter's house in Metuchen. He also tells them he's "sorry" about what happened with Vito, before sitting down to read the newspaper. However, soon Fat Dom starts making crude remarks about how he wonders if the pool cue that was found in Vito's rectum was "chalked", which Silvio sarcastically says is "very cute", even though he doesn't quite get it. Dom also says they found a hanky with Carlo's lipstick in Vito's pocket. When Carlo looks over at him, Fat Dom says he is just "breaking balls", but that he shouldn't laugh about a "tragedy". He then starts to talk about how the homosexual actor Ramon Novarro was found with an ivory dildo up his ass when he himself was murdered, remarking how "he was from Jersey too". Carlo and Silvio are fed up and tell him to go away, but Fat Dom then says "my mistake, Carlo's lipstick was on Vito's cock".
Silvio proceeds to strike him in the head with a dustbuster and holds him, telling Carlo to "hit the prick!". Instead, Carlo grabs a kitchen knife and stabs him in the gut. Fat Dom holds Silvio back and lunges at Carlo, who continues to stab him, as Silvio restrains him again. Carlo tells Dom "come here, you fuck!" and impales him with his knife one more time before he falls flat on the table, dead. Fat Dom's ringtone starts to sound, and Silvio is beyond irritated. He invents the excuse of a pipe breaking so he and Carlo can dispose of Dom's body. When Tony arrives at Satriale's later, Silvio tells him not to come in, and when he does, and sees Dom's body under the table cloth, he lifts his hands in the air and leaves Sil and Carlo to deal with it. It is later revealed that Carlo has been keeping Dom's severed head in his fridge for more than a month, and ultimately drives over to Connecticut where he kicks it down a sewer drain. During a sitdown with Phil and Tony later on, he asks him where Fat Dom has been, since he has disappeared and he was last seen in New Jersey, but Tony tells him "so was the Hindenburg, you might wanna look into that too!". However, after Phil suffers a heart attack, he decides to leave his conflicts with Tony, including Dom's whereabouts, behind.
- Dom has the Beethoven song "Für Elise" as a ringtone on his phone.
- The magazine Entertainment Weekly named Dom Gamiello's murder the "8th best death scene in the show's history".
- Actor Tony Cucci, who played the part of Gamiello, had been auditioning for the show for ten years prior to his casting. When he finally got the part, Cucci felt disappointed that he was going to get killed off so fast, but showrunner David Chase reassured him, telling him it "[would] be memorable".
Murders committed by Fat Dom