Bernadette is a former award-winning architect renowned for her innovative use of materials, now a socially isolated mother in Seattle. Known for her eccentric behavior, she is married to Elgin Branch and struggles with various personal challenges.

Elgin is a dedicated Microsoft engineer engrossed in his work, known for his highly popular TED Talk on artificial intelligence. He is Bernadette's husband and Bee's father, and his professional commitments sometimes distance him from family life.

Audrey is a deeply religious neighbor and leading figure among the parents at Galer Street School. She is critical of Bernadette and often finds herself in conflict with her.

Soo-Lin works at Microsoft as Elgin’s administrative assistant and is an active member of a self-help group. She is a close friend of Audrey Griffin and has significant personal developments throughout the story.

Jellinek is a professor of architecture who admires Bernadette's work and encourages her to reconnect with her creative passions. He is a key figure from her past in Los Angeles.

Dr. Kurtz is a psychiatrist at a private mental hospital, brought in by Elgin to assess Bernadette. She plays a crucial role during a pivotal intervention in the story.