During the meeting, Sonny, the family underboss, expresses interest in the deal, but Vito refuses the offer as he finds narcotics too much of a "dirty business". Barzini then approves Sollozzo's plan to have Vito murdered in the hopes that Sonny, as his father's successor, will accept the deal.
The Five Families and their associate, Sollozzo (aka The Turk) only wanted Don Vito Corleone dead when he refused their request for assistance, but when also realized that they could potentially reach an “arrangement” with Sonny Corleone if his father, the Don, was removed from the picture.
Why did Barzini plan to assassinate Michael Corleone? If he thought him so weak, surely it would have better to have him as head of a rival family, rather than someone strong. Barzini knew that he could manipulate and control Tessio. He wanted the Corleone crime family intact, making money, and kicking it up to him.
Barzini used the Tattaglia family as a pawn to approach Vito Corleone. When Vito refused to participate in the heroin trade, however Sonny showed disappointment in the decision, Barzini and Sollozzo secretly conspired with the other families to force the Corleones to open up their territory to drug trafficking.
In 1945, Barzini saw a new chance to achieve to supplant the Corleone family and gain dominance in New York, plotting with Virgil Sollozzo and Philip Tattaglia, the latter of whom he used as an unwitting scapegoat.
How did Vito Corleone figure out it was Emilio Barzini who was behind the assassination of Sonny Corleone? Because Barzini showed his cards when he followed up on Phillip Tattaglia's comments about the politicians and judges the Corleones were connected to during the meeting of the Five Families.
Most noteworthy, the novel depicts Clemenza's fatal heart attack (mentioned in The Godfather Part II), and the many conspiracy theories that he had actually been murdered by the Rosato Brothers, former Corleone soldiers who had formed their own gang after a dispute over the future of the family.
Hours later, Michael confronts Rizzi, saying he knows Rizzi set Sonny up to be murdered. He assures Rizzi that his life will be spared, but that he is being exiled from the family. Rizzi, believing he is safe, confesses that he conspired with Barzini.
Connie (who was unaware of her husband's role in Sonny's murder), hysterical after Carlo's death, blames Michael, denouncing him in front of his wife, Kay. In the novel, Connie quickly recovers from Carlo's demise, apparently relieved to be rid of an abusive, philandering husband.
Having Paulie brought to the Corleone compound Sonny Corleone deduced that Gatto had sold out his father. Sonny ordered Clemenza to have Gatto killed as soon as possible, saying he did not want to see Gatto again.
Some say that it was because he was afraid of Fanucci, others say that it was because he wanted to take over his territory. However, the most likely reason is that Vito knew that Fanucci was on his way out and didn't want him to have the chance to come back and take revenge.
Bruno later provided assistance to Sollozzo via police captain Mark McCluskey, who became Sollozzo's most trusted bodyguard and assisted a hit on Vito Corleone and tried to finish him off. His attempt failed and Sonny Corleone ordered Salvatore Tessio to kill Bruno.
It seemed easy because Vito Corleone and Luca Brasi made it easy for Sollozzo to murder Luca. A number of mistakes were made which led to Luca's death. Vito and Luca underestimated the enemy and how well they understood the situation. They mistakenly assumed Sollozzo would shoot him.
Paulie has seemingly betrayed Vito—and thus the family—by selling him out. In The Godfather, this kind of betrayal is the worst of all sins. We see the matter discussed, in the Corleone family office, just before the viewer spends time in front of Clemenza's cozy abode.
Fredo's decision is most likely a result of resentment toward Michael, by whom he felt he had been passed over. Michael was Fredo's "kid brother," and the fact that their father chose for Michael to take over the "family business" came as a great insult to Fredo, who was neither as intelligent nor as strong.
Ultimately, Tessio betrays Michael by helping arrange his assassination at a peace summit with Barzini and Philip Tattaglia. The summit will be held in Tessio's fiefdom in Brooklyn, where Michael will presumably be safe. In return, Tessio was to inherit the Corleone family upon Michael's death.
Hyman Roth, played in The Godfather: Part II by actor Lee Strasberg, was based on real-life mobster Meyer Lansky. Lansky is widely credited for coming up with some of the key innovations upon which the casino and gambling industry is built today.
A rift grows between Pentangeli and Michael, however, that eventually results in Pentangeli betraying the family. Pentangeli's character was created in The Godfather Part II by Coppola and Puzo due to actor Richard Castellano not reprising his role as Clemenza in the sequel.
At the Long Beach Causeway toll plaza, Barzini's men trap Sonny and shoot him to death. During a meeting with the other crime family dons to establish peace, Vito realizes that Barzini masterminded Sonny's murder. After Michael returns from Sicily, he assumes Sonny's place as Vito's heir apparent.
Luca Brasi is Don Vito Corleone's personal enforcer and the only man Vito himself fears. While slow-witted and brutish, Brasi is fiercely loyal with a reputation as a savage and remorseless killer.
That is the irony: Carlo did not ever betray Michael. He liked him well enough, and believed him when Michael told Carlo that he would be a key part of his inner circle with the Nevada transition. However, Carlo betrayed Sonny, which was no small matter. He set Sonny up for murder.
