Daniel is a twenty-five-year-old graduate student in 1967, writing his dissertation on the American Old Left movement. Originally born into the Isaacson family, he was adopted after his biological parents were arrested and executed for espionage. He displays a cynical, detached demeanor and struggles with the lasting trauma of his childhood. He often directs his internalized anger at his young wife and child as he investigates his family history.

Daniel's sister is a young woman profoundly shaped by the execution of their parents. Unlike her brother's academic detachment, she channels her grief into radical political activism, striving to uphold their parents' legacy through a dedicated foundation. She possesses a commanding presence but suffers from severe depression stemming from her chaotic upbringing.

Daniel and Susan's biological mother is an ardent communist raised in poverty on the Lower East Side. She views the need for a revolution with hardheaded pragmatism, contrasting with her husband's academic idealism. She despises the inequities of capitalist society and considers her political commitments a basic necessity for survival.

Daniel and Susan's biological father runs a small radio repair shop in the Bronx. He is an earnest Marxist-Leninist who studies communist theory and attempts to implement boycotts against major consumerist brands. His sincere idealism ultimately makes him a target during the Red Scare, leading to his arrest for espionage.

Daniel's nineteen-year-old wife and the mother of their young son. Raised in a comfortable New York family, she often feels alienated by the dark history of Daniel's family. She absorbs much of Daniel's cruelty but continually tries to repair their fractured relationship.

The adoptive father of Daniel and Susan. He is a gentle, Jewish lawyer who works with disenfranchised individuals and provides the siblings with a stable home after their parents' execution.

Daniel and Susan's adoptive mother. She works hard to offer a calm, middle-class life for the traumatized children, preferring to avoid discussions regarding their biological parents' history.

A dentist and former friend of the Isaacson family. His arrest and subsequent testimony in the espionage case become a central issue for Daniel, who despises the man for his role in his parents' downfall.

A respectable lawyer who defends Paul and Rochelle in their espionage trial. He also serves as a temporary guardian and advocate for young Daniel and Susan, attempting to keep them safe while fighting a losing battle against the state.

A charismatic, modern political activist associated with the 1960s counterculture. He believes in turning revolution into a heavily advertised product, utilizing mass media to spread his message rather than relying on traditional communist theories.

Selig Mindish's daughter, who grew up suffering the social fallout from her father's political entanglements. She has changed her identity to escape her past and harbors deep resentment toward the Isaacson family.

A therapist treating Susan at the mental health facility. He links her emotional struggles directly to her political activism, drawing Daniel's immediate anger.

Daniel and Phyllis's young son, named after his executed grandfather. He occasionally becomes a pawn in his father's psychological games and emotional outbursts.

The aunt of Daniel and Susan who briefly takes them in. Her reluctance to care for the children forces them into the state shelter system.

A reporter for The New York Times who writes an article reconsidering the Isaacsons' trial on its tenth anniversary. He approaches the case with a detached, journalistic perspective.

A magazine journalist and Artie Sternlicht's girlfriend. She participates in the counterculture movement alongside him.

Linda's fiancé, who presents himself as a pacifist but remains firmly protective of Linda against Daniel's aggressive questioning.

The widow of Ascher. She harbors a long-standing belief that the intense stress of defending the Isaacsons led directly to her husband's early death.