Mob boss Paul Vitti and his consigliere Dominic are discussing an upcoming meeting and the Mafia's present-day problems. Just as Dominic warns Vitti to look out for Primo Sindone (an up-and-coming mafioso who wants to be capo di tutti capi), gunmen drive past and kill Dominic.
Psychiatrist Ben Sobel is dealing with his own problems: his son from his first marriage listens to his sessions, his patients are not challenging enough, and his wedding to Laura MacNamara is coming soon. Sobel rear-ends a car belonging to Vitti and the trunk opens, revealing a man bound and gagged inside, which Sobel and his son do not notice. Jelly, one of Vitti's men, takes the blame, but Sobel gives Jelly his business card in case he changes his mind about compensation.
During a meeting, Vitti suffers a panic attack and tells Jelly that he needs to see a psychiatrist, but it has to be kept a secret. Jelly recommends Sobel. Vitti visits Sobel, claiming his friend needs therapy. Sobel impresses Vitti enough to want to see him whenever necessary. Sobel goes to Miami for his wedding and Vitti, Jelly, and the crew follow. Vitti explains he has been suffering from erectile dysfunction and Sobel suggests the source of the problem might be stress.
The next day Vitti has another panic attack and requests to see Sobel. Vitti explains his history with his father to Sobel, who thinks this might have something to do with Vitti's problems. The wedding is interrupted when an assassin is killed by one of Vitti's men. Sobel confronts Vitti and argues with him until he becomes angry. Sobel suggests he resolve his anger by calling Sindone and telling him how he feels. Vitti phones Sindone and starts by telling him how he feels but ends up threatening to kill him.
Sobel and his family return to New York, where they find a fountain in their garden, a gift from Vitti. The FBI arrive and request Sobel inform on Vitti, but he refuses. He changes his mind when the FBI play an altered tape in which Vitti reveals his intention to kill Sobel. At his next meeting with Vitti, Sobel wears a wire, but throws it away when he learns that, as a child, Vitti saw his father murdered. Vitti, informed that Sobel was working with the FBI, takes him to a secluded place to kill him. Sobel and Vitti get into an argument, and Vitti cries when reminded of his father's murder. Just then, two hitmen arrive to kill Vitti, but Jelly kills them both. Vitti apologizes for planning to kill Sobel, and the two reconcile.
The day of the meeting arrives, but Vitti has another panic attack. Jelly interrupts Sobel's wedding, requesting Sobel attend the meeting as Vitti's consigliere. Sobel is initially nervous, but his self-confidence grows to the point that he begins to patronize Primo until Primo finally pulls a gun. Vitti arrives, orders Primo to stand down, and announces he knows a traitor in his own family killed Dominic, but will not seek revenge and instead retire from the Mafia. Outside, a standoff ensues between Vitti's and Primo's men, during which Sobel takes a bullet intended for Vitti. The FBI intervenes, the mobsters are arrested, and Sobel is taken to the hospital.
Sobel visits Vitti in prison and Vitti thanks Sobel for his help before informing him that Primo Sindone was recently found dead. At home, Sobel dances with his new wife as Tony Bennett serenades them.