There are thirteen stories told in this book, which makes for a very difficult summary. This is especially true because each of the thirteen stories is narrated by a different character.
The book follows a large cast of mostly self-destructive characters as they grow older and fate sends them in directions they did not intend to go.
However, focusing on the two most prominent characters in the book, we can summarize A Visit from the Goon Squadas follows.
Sasha is introduced as a person in therapy for compulsive stealing. She is in her thirties at this point, works for Bennie Salazar at a record label, and lives in New York City. In her past, Sasha was a pickpocket in Naples, Italy after running away from home at the age of seventeen.
She returns to the US and enrolls at university in New York, meets Bennie at a Conduits concert, and lands a job with him. She spends years working at the record label, making no attempts to move up to become an executive. Sasha helps Bennie navigate his divorce to some extent and politely brushes him off when he desparately announces his love for her.
Later, she gets married to Drew, the boyfriend who was partially responsible for the drowning death of her suicidal best friend Rob when she was in college. She and Drew move to California and have two kids, Alison and Lincoln. Lincoln is slightly autistic.
Bennie Salazar was raised in California and loved music. He is introduced to a music mogul who is dating a friend of his when he (and his friend) is still in high school. Bennie plays bass guitar in a band that is not quite passable and he plays poorly. His interest in music and the music business, however, is passionate. Upon meeting the music mogul, Bennie launches his career in music, eventually becoming a wealthy music mogul himself.
Bennie marries Stephanie, has a child with her, and moves into a ritzy neighborhood outside of New York City. He is looked at with suspicion in the close-knit neighborhood while Stephanie finds ways to integrate herself.
They are divorced after Stephanie realizes that Bennie has slept with her tennis partner as a way to get revenge. Bennie then has awkward and often disappointing visits with his son.
Eventually Bennie remarries and has another child.