In the film, Fredo betrays Michael by telling their brother-in-law Johnny Ola that Michael plans to kill him. Johnny Ola then passes this information on to Hyman Roth, who orders Fredo's death. Michael learns of Fredo's betrayal and confronts him in a private meeting. Fredo begs for forgiveness but Michael refuses and orders him to be killed. Fredo is shot and killed by Al Neri in the film's final scene.
Fredo's death is a significant moment in the film as it marks the end of the Corleone family's innocence. Michael is forced to kill his own brother in order to protect his family and empire, and this act ultimately destroys him.