Matthew was Sean Gismonte's partner-in-crime and an associate in the Tony Soprano crew. He worked the executive card game along with Sean. He sold shares in Webistics through a stock brokerage operated by Christopher Moltisanti. The Webistics scam was a typical pump and dump exercise. They got into trouble with Chris for stealing nearby cars which could draw too much attention from the law. They also get into trouble for brutally beating up a broker and sending him to the hospital for recommending the sale of other stocks. Matt also did some burglary jobs with Chris and Sean. Furio and an associate visit Matt and Sean at their apartment for Tony's cut from the burglaries. During Furio's visit for Tony's cut, Sean and Matt act very unprofessionally by showing Furio their entire cut of money from the job hidden in a dresser. Upon seeing the money, Furio is prompted to demand 1,000 dollars from them for himself. Due to their lower status, Matt and Sean could not refuse. Furio jokingly remarks that they "suck each other's cocks" in Italian. He also leaves without closing the apartment door. This, combined with previous "disrespect" from mob superiors, heightened the already present urge to rapidly move up the ranks. During a meeting with Richie Aprile, they make fun of Chris' nose and also learn of Richie's disdain for Chris because Chris hit his niece Adriana. To gain respect from Richie and to quickly make their mark, Matt and Sean plan a hit on Chris.
Matt and Sean attempted a drive-by hit on Chris which resulted in Chris shooting Sean to death in self-defense. Chris was seriously wounded in the attack and rushed to the hospital. Matt ran away from the scene and went to Richie to tell him that the hit was done for him as a favor. Richie refused to protect Matt because he knew Tony would kill anyone involved in the attack. Richie chases Matt away with a baseball bat, calling him a pochie. Matt then goes into hiding. Eventually, Pussy learns of Matt's whereabouts from a teenager after implying that whoever tells them where he is hiding will receive "points" from the Soprano crew. Pussy also ends up paying the teenager $20. Pussy and Tony dragged a beaten Matt to a locked refreshment shack and after interrogating him to make sure that he and Sean were acting on their own, and not for someone else, shot him multiple times in the chest, stomach and head.
Cops later found Matt's dead body and a witness told officials about the gunshots he heard and saw two men leave the scene in a car. The witness identified Tony from a picture without knowing that he was a mob boss because the police had lied to him and told him that Tony was a mere crack dealer. When the witness learned that the murder was mafia-related, he then refused to cooperate and denied it was Tony Soprano who he had indeed witnessed. The feds continued to try to pin the murder on Tony, but remained unsuccessful. Tony repeatedly worried about being implicated in the show and felt as if he had "dodged a big bullet" when he got away clean.
- Appears in: "Guy Walks into a Psychiatrist's Office...", "Do Not Resuscitate", "The Happy Wanderer", "Full Leather Jacket", "From Where to Eternity", "Bust Out"
- Matt went to Pace College. He also obtained a stockbroker license, although he may have acquired it in a manner similar to Christopher, by paying someone else to take the test for him.
- The last drink Matt is given by Pussy prior to his execution is a diet Coke, referred to by Tony as a "sugarless motherfucker", despite being offered a Fanta.
- He was sometimes referred to as "Drinkwater"; "beve l'acqua" is Italian for "drink the water".